rt  OL  >y  /  C 


Library 


The  FORD 

STANDARD  ELECTRICAL 
EQUIPMENT 


STARTING  -  LIGHTING  -  IGNITION 


PUBLISHED  BY 

AMERICAN  BUREAU  OF  ENGINEERING,  Inc. 

t" 

1601-03  South  Michigan  Avenue 

CHICAGO,  U.  S.  A. 


Library 


Copyright  1919  by  the 

AMERICAN  BUREAU  OF  ENGINEERING,  INC. 

1601-03  S.  Michigan  Ave. 

Chicago,  111.,  U.  S.  A. 


A 


A 


iv 


PREFACE 

Many  Starting  and  Lighting  Systems  for  the  Ford  car 
have  been  made,  all  of  them  designed  to  be  installed  on  the 
car  after  it  left  the  Ford  factory.  This  fact  made  the  num- 
ber of  installations  limited.  Now,  however,  the  Ford  Com- 
pany is  beginning  to  install  a  starting  and  lighting  system 
on  its  cars  at  the  factory.  Ford  repairmen  will  need  com- 
plete and  detailed  explanations  and  repair  instructions. 

This  book  has  been  written  to  fill  this  need.  Every  de- 
tail of  the  starting  and  lighting  system  has  been  explained, 
and  the  numerous  illustrations  will  be  of  great  assistance 
in  simplifying  the  explanations  and  instructions. 

While  the  greater  portion  of  the  book  is  devoted  to  the 
starting  and  lighting  system,  a  full  description  of  the  igni- 
tion system  is  also  given,  with  diagrams  and  instructions 
for  making  tests. 

Troubles,  other  than  electrical,  which  may  arise  in  the 
operation  of  the  car,  are  also  explained  in  detail. 


405785 


ILLUSTRATIONS 

Figure 

No.  TITLE  Page 

1  Side  view  of  F.  A.  generator 1 

2  Side  view  of  F.  A.  starting  motor 2 

3  Looking  at  generator  frame  with  end  housing  re- 

moved       5 

4  Front  end  view  of  generator   6 

5  Looking  at  inside  of  generator  rear  end  housing  7 

6  Generator  brushes  and  field  coils 9 

7  Right  and  wrong  way  to  sandpaper  brushes 10 

8  Rear  end  view  of  generator 11 

9  Generator  armature    12 

10  Ammeter  in  series  with  generator    14 

11  Looking  at  back  of  generator  brush  ring 15 

12  Looking  at  front  end  of  starting  motor 18 

13  Looking  at  inside  of  motor  rear  end  housing 19 

14  Looking  at  front  end  of  motor  frame 20 

15  Motor  brushes  and  field  coils 21 

16  Motor    armature 22 

17  Early  type  lighting  and  ignition  switch 33 

18  Later  type  lighting  and  ignition  switch 34 

19  Wiring  diagram,  with  cutout  on  dash 37 

19-A     Wiring  Diagram,  with  cutout  on  generator 38 

19-B     Circuit    diagram     39 

20  F.  A.  installation  on  Ford  car  (right  side) 40 

21  F.  A.  installation  on  Ford  car  (left  side) 42 

22  Ammeter  in  series  with  battery  for  Tests  1  and  2  49 

23  Ammeter  in  series  with  battery  for  Test  3 51 

24  Circuits  for  Test  1,  cutout  on  dash 53 

24-A     Circuits  for  Test  1,  cutout  on  generator 54 

24-B     Internal  connections  of  cutout  on  generator 55 

25  Circuit  tester,  using  a  110-volt  lamp 57 

26  Circuit  tester,   using  a   6-volt  lamp 57 

27  Lighting  circuit    65,  69,  71 

28  Charging  circuit.    Cars  with  cutout  on 

dash    77,  84,  87, 103 

vi 


Figure 

No.                            TITLE  Page 
28-A  Charging    circuit.      Cars    with    cutout    on    gener- 
ator    78,  85,  88, 104 

29  Special   test   connections   for   Test   3 79 

29-A  Special  test  connections  for  Test  3 80 

30  Measuring   voltage    of   generator 86 

31  Testing  armature  for  opens  and  shorts 93 

32  Testing  entire  field  for  open  circuit 95 

33  Testing  each  field  coil  for  open  circuit 96 

34  Testing  entire  field  for  ground 97 

35  Testing  each  field  coil  for  ground 98 

36  Circuit  tester,  using  an  ammeter 99 

37  Testing  each  field  coil  for  short  circuit 100 

38  Testing  for  reversed  field  coil 101 

39  Starting  motor  circuits   107 

40  Circuit  diagram  of  Ford  Ignition  System 113 

41  Magnets  of  Ford  magneto    114 

42  Circuit  diagram  of  a  Ford  ignition  coil 115 

43  Circuit  tester,  using  a  voltmeter 122 


vii 


INDEX 

Page 
Ammeter,  Ford 

Description  of  3 

Location   of    31 

Purpose    of    31 

Ammeter,  Test 

Connecting,  in  series  with  battery  for  testing.     Tests 

1  and  2    48 

Connecting,  in  series  with  battery  for  testing.     Test 

3     50 

Battery  Troubles    65,  71,  85, 109 

Carbon    in    Engine    129 

Changing  position  of  third  brush 14 

Charging  current,  regulation  of   13, 14 

Charging  rate    14 

Circuits 

Charging  44 

Generator  field  current  46 

Ignition   43 

Lighting    45 

Starting     41 

Coils,  Ignition 

Description  of   116 

Tests  on    119, 120 

Commutator,  Ignition 

Description  of 117 

Setting 128 

Tests  on    120 

Cutout 

Action  of 28 

Adjustment   of    29 

Description  of  2 

Location   of    25 

On  Dash    26 

On   Generator    26 

Path  of  current  through  27 

Tests  on   54,  82 

viii 


Page 

Engine  not  Running,  Lamps  Off 

Chart  1   53 

Testing  for  trouble  under  these  conditions 49 

Troubles  that  occur  under  these  conditions 47 

Engine  not  Running,  Lamps  On 

Chart  3    65 

Chart  4 69 

Chart  5 71 

Testing  for  trouble  under  these  conditions 49 

Troubles  that  can  occur  under  these  conditions 47 

Engine  Running,  Lamps  Off 

Chart  7    77 

Chart  8    84 

Chart  9    87 

Chart    10     103 

Testing  for  trouble  under  these  conditions 50 

Troubles  that  can  occur  under  these  conditions 48 

Engine  or  Power  Plant  Troubles 

Backfiring    126 

Engine  action  irregular 138 

Engine  loses   power    138 

Engine  misfires    122 

Engine  refuses  to  start  118 

Engine  sluggish   134 

Knocking    129 

Fluctuating  Ammeter  Pointer  when  Testing  for  Trouble  51 

Generator 

Armature    12 

Brushes     8 

Changing  position  of  third  brush 14 

Description  of  1 

Drive    4 

Field  Windings  12 

Frame    6 

How  to  remove,  from  car 16 

How   to   take   apart    17 

Location   and    Mounting    4 

Lubrication    4 

Performance 16 

Regulation  of  Charging  Current 13 

Reversal   of    86 

Troubles  in   88  to  102 

How  to  remove  generator  from  car 16 

ix 


Page 

How  to  remove  starting  motor  from  car • 23 

How  to  take  generator  apart 17 

How  to  take  starting  motor  apart 24 

Ignition  System 

Coils   116 

Commutator   117, 128 

Description  of   112 

Magneto     112, 118 

Tests  on  coils 119, 120 

Tests   on    commutator    120 

Troubles  in 117,  124, 128 

Lamps 

Burned   out    55,  G2 

Description    of 36 

Troubles   in    52,  72 

Lighting  and  Ignition  Switches 

Description    of    3,  32 

Tests    on     62,  67 

Troubles  in  early  type  of 32 

Locating  missing  cylinder  123 

Lubrication  of  generator  4 

Lubrication  of  starting  motor 18 

Magneto 

Description    of    112 

How  to  remove 115 

Tests  on  Coils  119 

Performance  of  Generator 16 

Performance  of  Starting  Motor    22 

Regulation  of  Charging  Current   13, 14 

Special  instructions  for  lamp  troubles 52 

Starting  Motor 

Armature    22 

Brushes     20 

Description  of 2 

Drive    18 

Field   Windings    21 

Frame 19 

How  to  Remove  from  car 23 

How  to  take  apart   24 

Location   and    Mounting    18 

Lubrication    18 

Performance    22 

Troubles  in   .  109 


Page 

Starting  Switch 

Construction     36 

Description     4 

Location 36 

Purpose 36 

Test    on 60 

Starting  Troubles 

Chart  12 107 

Description  of   48 

Testing  for   52 

Testing  for  Troubles 48 

Third  Brush,  Changing  position  of 14 

Troubles  in  Starting  and  Lighting  System 46 

Troubles  in  Engine  or  Power  Plant 

Backfiring  126 

Engine  action  irregular 138 

Engine  loses  power   138 

Engine   misfires 122 

Engine   refuses  to  start    118 

Engine  sluggish    134 

Knocking     129 

Wiring  of  Electrical  Units   36 


xi 


AMBU   KEY   NUMBERS. 

In  making  the  regular  Ambu  tests  on  the  F.  A.  Starting 
and  Lighting  System,  the  Key  Numbers  are  as  follows: 

UPPER:  Use  9  when  engine  is  running  at  speed  which 
would  drive  car  at  20  miles  per  hour  in  high  speed. 

LOWER:  (a)  Use  4  when  tail  lamp  and  large  bulbs  in 
headlights  are  burning. 

(b)  Use  2  when  tail  lamp  and  small  bulbs  in  headlamps 
are  burning. 

TESTS. 

The  regular  tests  with  Ambu  are  made  just  as  on  any  other 
car. 

WHAT   CHARTS    TO   USE. 

Chart  1,  Page  53. 

ENGINE    NOT    RUNNING,    LAMPS    OFF. 
Consult  this  chart  if  you  find  that  battery   is  discharging 
when  engine  is  not  running,  and  all  lamps,  and  the  ignition 
is  turned  off. 

Chart  2,  Page  64. 

ENGINE    NOT    RUNNING,    LAMPS    OFF. 
Consult  this  chart  if  pointer  goes  backward  when  you  con- 
nect meter  in  series  with  the  battery  for  making  tests. 

Chart  3,  Page  65. 

ENGINE  NOT  RUNNING,  LAMPS  ON. 

Consult  this  chart  if  no  lamps  burn  when  switch  is  turned 
on. 

Chart  4,  Page  69. 

ENGINE  NOT  RUNNING,  LAMPS  ON. 

Consult  this  chart  if  your  ammeter  connected  in  series  with 
battery  indicates  more  than  5.4  amperes  when  tail  lamp  and 
large  bulbs  in  headlamps  are  burning,  or  more  than  1.25  am- 
peres when  tail  lamp  and  small  bulbs  in  headlamps  are  burn- 
ing. 

Chart  5,  Page  71. 

ENGINE  NOT  RUNNING,  LAMPS  ON. 

Consult  this  chart  (a)  when  some  of  the  lamps  do  not  burn 
when  switch  is  turned  on,  (b)  when  some  or  all  of  the  lamps 
burn  dimly  when  switch  is  turned  on. 
Chart  6,  Page  76. 

ENGINE  NOT  RUNNING,  LAMPS  ON. 

Consult  this  chart  if  your  ammeter,  connected  in  series 
with  the  battery,  reads  backwards  when  the  lamps  are  turned 
on. 

xii 


Chart  7,  Page  77. 

ENGINE  RUNNING,   LAMPS   OFF. 

Consult  this  chart  if  your  ammeter,  connected  in  series 
with  the  battery,  indicates  that  battery  is  not  receiving  any 
charging  current.  Run  engine  on  magneto,  and  turn  off  all 
lamps  when  making  this  test. 

Chart  8,  Page  84. 

ENGINE   RUNNING,   LAMPS   OFF. 

Consult  this  chart  if  your  ammeter,  connected  in  series  with 
the  battery,  indicates  that  battery  is  discharging  instead  of 
being  charged  when  lamps  are  off,  and  engine  is  run  on  the 
magneto. 

Chart  9,  Page  87. 

ENGINE  RUNNING,   LAMPS   OFF. 

Consult  this  chart  if  your  ammeter,  connected  in  series  with 
the  battery,  indicates  that  generator  is  receiving  less  than  10 
.amperes  charging  current  when  lamps  are  turned  off,  and 
engine  is  run  on  magneto. 

Chart  10,  Page  103. 
ENGINE  RUNNING,   LAMPS   OFF. 

Consult  this  chart  if  your  ammeter,  connected  in  series  with 
the  battery,  indicates  that  battery  is  receiving  more  than  10 
amperes  charging  current  when  lamps  are  turned  off,  and  en- 
gine is  run  on  magneto. 

Chart  11,  Page  105. 

Consult  this  chart  is  the  pointer  on  your  ammeter,  connected 
in  series  with  the  battery,  jumps  about  from  place  to  place  on 
the  scale  of  the  ammeter,  and  does  not  come  to  rest. 

Chart  12,  Page  107. 
STARTING  TROUBLE. 

Consult  this  chart  if  the  starting  motor  does  not  turn  over 
the  engine,  or  turns  it  over  too  slowly  for  engine  to  start. 


Xlll 


Ford    Starting   and    Lighting 
System 

The  Ford  Starting  and  Lighting  System  with  which 
Ford  cars  are  equipped  at  the  Factory  is  made  up  of  the 
following  parts: 


FIGURE  1. 

SIDE    VIEW   OF   FA    GENERATOR. 

A  is  Main  Generator  Frame.  B  is  cover  over  rear  end  hous- 
ing. C  is  driving  pinion.  D  is  front  end  cap.  E  is  generator 
terminal.  F  are  screws  which  hold  B  in  place.  H  are  screws 
lohich  hold  rear  end  housing  in  place.  I  is  rear  bearing  oiler. 
K  are  screws  which  hold  brush  ring  in  place.  L  are  screws 
which  hold  field  poles  in  place. 

1.  THE  GENERATOR,  Figure  1,  which  (a)  charges 
the  battery  when  the  engine  is  running,  (b)  Furnishes 
the  current  used  by  the  lamps  when  the  engine  is  run- 
ning at  a  speed  of  over  12  miles  per  hour,  (c)  May  be 
used  to  furnish  the  current  used  by  the  ignition  coils 
when  the  engine  is  running,  although  the  regular  Ford 


DESCRIPTION  OF  PARTS 


magneto  should  be  used  for  this  purpose, 

2.  THE  STARTING  MOTOR,  Figure  2,  which  does  the 
work  ordinarily  done  by  the  hand  crank — turns  the  en- 
gine over  fast  enough  when  starting  to  enable  it  to  begin 
to  run  under  its  own  power.  The  starting  motor  is  used 
only  to  crank  the  engine,  and  is  not  in  operation  after  the 
engine  is  running  under  its  own  power. 


FIGURE  2. 

SIDE   VIEW  OF  FA   STARTING  MOTOR. 
A  is  Motor  Terminal.     B  is  cover  over  rear  end  housing. 
C  are  screws  which   hold  B  in  place.     D   are  screws  which 
hold  rear  end  housing  in  place. 

3,  THE  STORAGE  BATTERY,   which    (a)    furnishes 
the  current  that  causes  the  starting  motor  to  crank  the 
engine,     (b)    Furnishes  current  for  the  lamps  when  the 
engine  is  not  running,     (c)    Furnishes  current  for  the 
ignition  coils  when  the  engine  is  started. 

4.  THE   AUTOMATIC   ELECTRICALLY    OPERATED 
SWITCH,  OR  "CUT-OUT"  as  it  is  usually  called,  which 
automatically  connects  the  generator  to  the  battery  as 


DESCRIPTION"  OF  PARTS 


soon  as  the  voltage  of  the  generator  is  slightly  greater 
than  that  of  the  battery,  and  which  automatically  dis- 
connects the  generator  from  the  battery,  as  the  engine 
slows  down,  when  the  voltage  of  the  generator  becomes 
less  than  that  of  the  battery.  The  cut-out  does  NOT  dis- 
connect the  generator  from  the  battery  when  the  battery 
is  fully  charged. 


5.  THE    AMMETER,    mounted    on    the    instrument 
board  in  front  of  the  driver.    This  is  an  electrical  instru- 
ment which  indicates  the  strength  of  the  current  passing 
in  or  out  of  the  battery.    The  ammeter  has  a  pointer  which 
moves  over  a  scale  marked  directly  in  amperes.    The  zero 
line  on  the  scale  of  the  ammeter  is  on  the  center  line  of 
the  scale.    The  maximum  indication  shown  on  this  meter 
is  20  amperes.     The  readings  to  the  left  of  this  zero  line 
are  marked  "Charge".    This  means  that  when  the  genera- 
tor is  delivering  current  to  or  is  "charging"  the  battery, 
the  pointer  moves  to  the  left  of  the  zero  line,  coming  to 
rest  over  a  line  on  the  scale  which  gives  the  number  of 
amperes  charging  current  which  is  passing  into  the  bat- 
tery.   When  the  battery  is  not  receiving  any  current  from 
the  generator,  but  is  furnishing  current  to  operate  the 
lights  or  ignition  coil, — and  hence  is  "discharging", — the 
pointer  of  the  ammeter  will  swing  to  the  right  of  the  "0" 
line  to  the  part  of  the  scale  which  is  marked  "discharge". 
The  pointer  will  come  to  rest  over  a  line  which  indicates 
how  many  amperes  current  is  being  furnished  by  the  bat- 
tery to  the  lights  or  ignition  coils. 

6.  THE  COMBINATION  LIGHTING  AND  IGNITION 
SWITCH,  which  enables  the  driver  to  turn  the  lights  on 
or  off,  and  to  connect  the  ignition  coils  to  either  the  bat- 
tery or  magneto  or  to  disconnect  them  from  battery  or 
magneto.    This  is  located  on  the  instrument  panel  in  front 
of  the  driver, 


DESCRIPTION  OF  PARTS 


7.  THE  STARTING  SWITCH,  which  is  operated  by 
the  driver's  foot,  and  which  enables  the  driver  to  connect 
the  starting  motor  to  the  battery  in  order  that  it  may 
crank  the  engine,  and  to  disconnect  the  starting  motor 
from  the  battery  after  the  engine  is  running  under  its  own 
power.     The  switch  is  located  under  the  floorboards  in 
front  of  the  driver. 

8.  THE  LARGE  AND  SMALL  LAMPS  in  the  head- 
lights and  the  tail  lamp. 

9.  THE  WIRES  AND  CABLES  which  connect  together 
the  various  parts  and  units  together. 

The  parts  will  be  described  in  the  order  named. 


1.     THE  GENERATOR. 

LOCATION  AND  MOUNTING.  The  generator  is  lo- 
cated on  the  right  side  of  the  engine  at  the  front  end. 
See  N.  Figure  20.  It  is  bolted  to  the  cylinder  front  end 
cover,  with  three  standard  three-eighth  inch  cap  screws 
with  seven-sixteenth  standard  heads.  A  paper  gasket 
(See  0.  Figure  4)  is  placed  between  the  generator  and  the 
cylinder  cover  to  prevent  oil  leaks. 

DRIVE.  Mounted  on  the  front  end  of  the  generator 
shaft  is  a  pinion  having  16  teeth  cut  spirally.  See  C. 
Figure  1.  This  pinion  engages  with  the  large  timer  gear. 
The  generator  runs  at  one  and  one-half  times  the  engine 
speed. 

LUBRICATION.  Both  front  and  rear  generator  bear- 
ings are  equipped  with  ball-bearings.  The  front  ball-bear- 
ing is  lubricated  by  oil  splashing  from  the  timer  gear. 
At  the  rear  end  housing  of  the  generator  is  an  oil  cup 
(Shown  at  I  in  Figure  1)  through  which  oil  may  be 
squirted  to  lubricate  the  rear  ball  bearing.  A  few  drops 


DESCRIPTION  OF  PARTS 


of  oil  should  be  squirted  in  this  oiler  occasionally.  To  do 
this  turn  the  knurled  head  on  the  oiler  to  the  right  as  far 
as  it  will  go.  This  will  uncover  an  oil  hole  through 
which  the  oil  may  be  applied.  When  the  knurled  head 
is  released  a  spring  rotates  it  back  into  place,  covering  the 


FIGURE  3. 
LOOKING  AT  GENERATOR  FRAME  WITH  END  HOUSING 

REMOVED. 

A  is  a  field  lead  which  is  connected  to  the  third  brush.  B 
is  armature  lead  which  is  connected  to  main  ungrounded 
brush.  C  is  field  lead  which  is  connected  to  grounded  main 
brush.  E  is  generator  terminal.  F  are  insulating  bushings 
around  generator  terminals.  H  are  the  shunt  field  coils.  I 
are  two  of  the  field  pole  pieces. 

oil  hole.  Always  be  sure  that  this  oil  hole  is  covered  after 
applying  the  oil,  so  as  to  keep  dirt  out  of  the  oil.  Do  not 
oil  the  rear  bearing  too  often  as  the  oil  will  be  thrown 
on  the  commutator,  get  under  the  brushes  and  prevent  the 
generator  from  charging  the  battery.  A  great  deal  of  the 


DESCRIPTION  OF  PARTS 


trouble  with  the  generator  is  due  to  excessive  oiling. 
There  is  a  round  felt  washer  pressing  against  front  and 
rear  ball-bearings,  the  purpose  of  which  is  to  keep  oil  off 
the  commutator  and  other  parts  where  it  does  not  belong. 
If  too  much  oil  is  used,  however,  it  will  work  past  these 
washers  and  collect  on  the  commutator  and  other  parts. 


FIGURE  4. 

FRONT  END  VIEW  OF  GENERATOR. 
C  is  driving  pinion.  D  is  front  end  cap.  E  is  generator 
terminal.  H  are  screws  which  hold  rear  end  housing  in  place. 
M  are  screws  which  hold  front  end  cap  in  place.  N  are  holes 
into  which  are  turned  the  screws  with  which  the  generator 
is  held  in  place  on  the  car.  0  is  paper  gasket. 

FRAME.  The  main  portion  of  the  frame  (Shown  at  A 
in  Figure  1)  is  made  of  a  wrought  iron  pipe,  having  an 
outside  diameter  of  4y2  inches,  inside  diameter  of  3-31/32 
inches,  and  length  of  4-7/16  inches.  Bolted  to  the  inside 
of  the  frame  are  four  steel  pole-pieces  over  which  the  field 


DESCRIPTION  OF  PARTS 


coils  are  wound.  These  pole  pieces  are  arranged  as  shown 
in  Figure  3.  Each  pole  piece  is  held  in  place  by  a  flat 
head  machine  screw.  These  screws  are  prevented  from 
turning  by  a  center-punch  mark  on  the  edge  of  the  heads. 


FIGURE  5. 
LOOKING     AT     INSIDE     OF     GENERATOR     REAR     END 

HOUSING. 

A  is  the  "3d"  brush  holder.  B  is  the  ungrounded  main 
brush  holder.  C  is  the  grounded  main  brush  holder.  D  is  fiber 
insulating  the  third  brush  and  ungrounded  main  brush 
from  the  brush  ring,  E.  F  is  narrow  ring  which  clamps 
brush  ring  in  place  by  means  of  four  screws,  as  shown,  whose 
heads  are  shown  at  K  in  Figure  8. 

If  the  pole  pieces  are  removed  to  work  on  a  field  coil,  be 
sure  to  make  another  center-punch  mark  when  you  reas- 
semble the  pole  piece  to  prevent  the  screw  from  turning. 
Each  pole  face  is  2y8  inches  long,  measured  from  front  to 


DESCRIPTION  OF  PARTS 

rear.    The  "field  bore",  or  the  diameter  measured  between 
the  opposite  pole  faces  is  about  2%  inches. 

At  the  front  end  of  the  frame  is  a  flat  cast  iron  end  cap 
(shown  at  D  in  Figures  1  and  4)  which  carries  the  front 
bearing,  and  which  contains  the  holes  shown  at  N  in 
Figure  4,  into  which  are  turned  the  bolts  which  fasten 
the  generator  to  the  engine.  This  end  cap  is  fastened 
to  the  generator  frame  by  six  screws  (shown  at  M  in 
Figure  4)  which  turn  into  the  front  end  of  the  frame. 
These  screws  may  be  removed  with  a  screw  driver  when 
it  is  desired  to  remove  the  end  cap  and  armature.  At  the 
rear  end  of  the  generator  is  a  removable  U  shaped  housing, 
as  shown  in  Figure  5.  This  carries  the  rear  end  bearing 
and  the  brush  ring.  It  may  be  removed  by  taking  out 
four  screws,  two  of  which  are  shown  at  H  in  Figure  1. 
As  seen  in  Figure  5,  there  are  four  openings  in  this  hous- 
ing through  which  the  commutator,  brushes,  and  wiring 
may  be  examined.  In  removing  this  housing  be  careful 
not  to  crack  the  insulation  (shown  at  F  in  Figure  3), 
which  is  placed  around  the  generator  terminal.  Fitting 
over  this  housing  is  a  sheet  iron  cover  which  closes  up 
the  four  holes.  This  cover  is  shown  at  B  in  Figure  1.  It 
is  held  in  place  by  two  screws,  shown  at  F  in  Figure  1. 

BEUSHES.  There  are  three  carbon  brushes,  as  shown 
in  Figures  5  and  6.  The  two  lower  ones  carry  the  charg- 
ing current  out  of  and  into  the  armature.  The  upper  one 
is  called  the  "third"  brush,  and  connects  to  one  end  of 
the  field  as  shown  in  Figure  6.  The  two  lower  brushes 
are  %  inch  wide,  %  inch  long,  and  13/16  inch  high.  The 
third  brush  is  3/16  inch  wide,  %  inch  long,  and  13/16 
inch  high.  The  most  important  work  on  the  brushes  is  to 
keep  the  surface  which  bears  on  the  commutator  perfectly 
clean,  and  rounded  off  so  that  every  point  of  the  brush 
surface  touches  the  commutator.  This  may  be  done  by  in- 
serting a  piece  of  fine  sandpaper  (never  use  emery  cloth) 
between  the  brush  and  the  commutator,  with  the  sanded 
side  toward  the  brush.  Then  move  sandpaper  back  and 


DESCRIPTION  OF  PARTS 


forth  as  shown  at  B  in  Figure  7,  until  the  brush  surface  is 
clean  and  rounded.  After  sandpapering,  or  "sanding"  the 
brushes,  it  is  best  to  run  the  engine  for  about  twenty  min- 
utes before  making  any  test  readings  on  the  generator. 

It  is  also  important  that  each  bare  copper  pigtail  be 
fastened  securely  to  the  brush,  and  connected  firmly  to  the 
brush  holder.  See  that  the  end  of  each  brush  spring  bears 
firmly  and  squarely  on  the  top  end  of  the  brush,  and  that 
the  end  is  not  bent  so  that  it  rests  on  the  brush  holder  in- 
stead of  on  the  brush,  and  so  that  it  does  not  bear  against 


INSULATED 
BRUSH 


LOOKING  AT  INSIDE  OF  END  CAP 


FIGURE  6. 
GENERATOR    BRUSHES    AND    FIELD    COILS. 

the  side  of  the  brush  instead  of  the  top,  thus  preventing 
the  brush  from  touching  the  commutator.  The  spring  ad- 
justment and  position  may  be  tested  by  raising  the  brush 
a  short  distance  by  means  of  the  pigtail  and  then  suddenly 
releasing  it.  The  brush  should  snap  back  on  the  commuta- 
tor and  strike  the  commutator  with  a  click. 

The  pigtail  is  fastened  to  the  brush  holder  in  each  case 
with  a  round  head  machine  screw.  The  end  fastened  by 
this  screw  is  soldered  into  a  flat  terminal  which  fits  under 
the  head  of  the  screw.  The  brush  holders,  shown  at  A, 


DESCRIPTION  OF  PARTS 


B  and  C  in  Figure  5  are  made  of  aluminum.  The  two 
lower,  or  main  brush  holders  are  riveted  to  a  flat  ring, 
and  cannot  be  moved  relative  to  each  other.  The  third 
brush  holder  is  bolted  through  a  slot  in  this  ring,  as 
shown  at  A  in  Figure  11.  The  nut  on  this  bolt  may  be 
loosened,  thus  allowing  the  bolt  to  be  moved  to  any  posi- 
tion in  the  slot.  In  this  way  the  third  brush  holder  is 
moved,  and  the  brush  may  be  made  to  bear  on  different 
points  of  the  commutator.  This  feature  will  be  discussed 
more  fully  later. 

BRUSH 


SANDPAPER 


DO  N0T  HOLD  SANDPAPER 
IN  THIS  WAV 


WRONG  &  RIGHT  WAY  TO  HOUP  SANDPAPER  IN  CLEAIsMNa    BRUSHES 

FIGURE  7. 

The  main  brush  holder  shown  at  B  in  Figure  5,  and  the 
third  brush  holder,  shown  at  A  in  Figure  5,  are  insulated 
from  the  ring  by  a  strip  of  fiber  but  the  main  brush 
holder  shown  at  C  in  Figure  5  is  riveted  directly  to  the 
metal  of  the  brush  ring,  and  is  thus  "grounded"  to  the 
ring. 

On  the  inner  circumference  of  the  brush  ring  are  four 
slots  as  shown  at  B  in  Figure  11.  Bearing  against  the 
brush  ring  is  a  smaller  ring  which  is  seen  when  looking 
at  the  brushes  and  toward  the  inside  of  the  end  housing. 
This  small  ring  has  four  screw  holes  into  which  four 

10 


DESCRIPTION  OF  PARTS 

round  head  screws  are  turned.  These  screws  are  inserted 
through  holes  in  the  end  cap  of  the  generator,  as  shown 
at  K  in  Figure  8.  These  screws  pass  through  the  slots 
cut  in  the  inner  circumference  of  the  brush  ring,  and 
when  they  are  turned  in,  clamp  the  small  ring  against 
the  brush  ring,  which  is  in  this  manner  held  in  place 


FIGURE  8. 

REAR  END   VIEW  OF  GENERATOR. 

E  is  generator  terminal.  H  are  two  of  the  screws  that  hold 
rear  end  housing  in  place.  K  are  screws  which  hold  brush 
ring  in  place. 

rigidly.  If  the  four  screws  shown  at  K  in  Figure  8  are 
loosened,  the  entire  brush  ring  may  be  rotated  as  far  as 
the  length  of  the  slots  in  the  brush  ring  will  permit. 

The  springs  which  press  the  brushes  against  the  com- 
mutator are  made  of  flat  spring  steel.  One  end  of  each 
spring  is  fastened  in  a  slotted  stud.  The  spring  is  coiled 

$      11 


DESCRIPTION  OF  PARTS 

into  several  turns  and  the  free  end  bears  on  the  upper 
end  of  the  brush.  The  stud  which  holds  one  end  of  the 
spring  is  fastened  rigidly  to  the  brush  holder.  The  con- 
struction is  shown  in  Figure  5. 

FIELD  WINDINGS.  On  each  of  the  four  field  poles 
is  wound  a  single  field  coil.  The  four  coils  are  con- 
nected in  series,  as  shown  in  Figures  3  and  6.  The  joints 


FIGURE  9. 

GENERATOR   ARMATURE. 

A-B  is  commutator.     C  is  driving  pinion.    D  is  front  end 
cap.    E  is  armature  core. 


between  successive  coils  are  made  by  soldering  the  wires 
together  and  covering  the  joint  with  tape.  The  resistance 
of  the  four  coils  when  cold  is  about  2.45  Ohms.  In  order 
to  disconnect  the  field  coils  from  each  other,  the  tape 
must  be  removed  and  the  joint  unsoldered. 

ARMATURE.     The   generator   armature   is   shown   in 
Figure  9.    It  has  21  slots,  and  21  segments  on  the  com- 

12 


DESCRIPTION  OF  PARTS 

imitator.  The  wires  are  cotton  covered  enameled  wire. 
The  only  part  of  the  armature  that  requires  attention  is 
the  commutator  upon  which  the  brushes  bear.  This 
should  be  kept  clean,  smooth,  and  free  from  oil.  If  the 
rear  end  bearing  on  the  generator  is  not  given  too  much 
oil,  there  will  be  no  trouble  caused  by  an  oily  commu- 
tator. Never  put  any  grease,  graphite,  or  other  lubri- 
cant on  the  commutator.  To  clean  a  dirty  commutator, 
first  hold  a  dry  rag  against  it  while  the  engine  is  running. 
This  will  remove  most  of  the  dirt.  To  finish,  hold  a  rag 
moistened  with  gasoline  against  the  commutator.  This 
will  remove  all  remaining  dirt.  Do  not  use  too  much 
gasoline  on  the  rag,  and  always  run  the  engine  after- 
wards for  several  minutes  with  the  cover  removed  from 
the  rear  end  housing.  This  is  to  drive  off  any  gasoline 
vapor. 

The  space  between  segments  should  be  kept  free  from 
oil,  grease,  and  bits  of  carbon  and  copper.  To  clean  these 
spaces,  use  a  sharp  pointed  tool,  and  scrape  out  the  dirt 
until  the  clean  mica  shows  the  entire  length  of  the  seg- 
ment, between  the  points  marked  A  and  B  in  Figure  9. 
The  mica  should  be  cut  down  until  it  is  about  1/32  inch 
below  the  surface  of  the  commutator. 

If  the  commutator  is  rough  or  scratched,  it  may  be 
made  smooth  by  holding  a  piece  of  fine  sandpaper  against 
it,  while  the  engine  is  running,  until  it  is  perfectly 
smooth.  After  doing  this,  examine  the  spaces  between 
segments  to  make  sure  that  no  particles  of  copper  have 
lodged  in  them. 

REGULATION  OF  CHARGING  CURRENT.  The 
strength  of  the  current  delivered  by  the  generator  is  reg- 
ulated by  the  "Third  Brush"  system.  The  field  winding 
is  connected  between  the  grounded  main  brush  and  the 
small  "third"  brush  (shown  in  Figure  6)  which,  as 
already  described,  bears  on  the  upper  part  of  the  com- 
mutator. The  position  of  this  brush  may  be  changed  so 
that  the  brush  may  be  brought  nearer  to  or  farther  from 

13 


DESCRIPTION  OF  PARTS 

the  grounded  main  brush.  The  distance  between  these 
two  brushes,  or  in  other  words  the  number  of  commu- 
tator segments  that  the  "third"  brush  is  away  from  the 
grounded  main  brush,  determines  the  maximum  strength 
of  the  current  delivered  by  the  generator.  The  strength 
of  the  current  may  be  varied  from  8  to  12  amperes. 

When  it  is  desired  to  change  the  maximum  generator 
current,  an  ammeter  should  always  be  connected  in  the 
circuit  between  the  battery  and  the  generator.  This  is 
most  easily  done  at  the  generator,  as  shown  in  Figure  10. 

AMMETER    HAVING 
ABOUT  A  25  AMPERE 
SCAO_E        ./ 


GENERATOR 


WIRE    DISCONNECTED   FROM 
GENERATOR    TERMINAL. 


\ 
GENERATOR    TERMINAL- 


CONNECTING   AN  AMMETER   IN  SERIES  WITH   GENERATOR   WHEN 
CHANGING    POSITION   OFTHE  THIRD   BRUSH 

FIGURE  10. 


In  this  figure  the  connections  are  shown  for  cars  in  which 
the  cutout  is  mounted  on  the  dash.  On  cars  having  cut- 
out on  generator,  disconnect  the  wire  from  the  "B"  ter- 
minal on  the  cutout.  Fasten  this  wire  to  the  " — "  or 
"25"  post  of  your  ammeter.  Then  connect  the  "+"  post 
on  your  meter  to  the  "B"  terminal  on  the  cutout.  The 
generator  should  be  warm  when  the  change  is  made. 
All  lights  should  be  turned  off  and  the  engine  should  be 
run  on  the  magneto.  Remove  the  cover  which  closes  up 
the  openings  in  the  rear  end  housing  of  the  generator. 


DESCRIPTION  OF  PARTS 

This  is  done  by  taking  out  two  round  head  screws,  as 
shown  at  F  in  Figure  1.  The  nut  which  holds  in  place 
the  bolt  which  clamps  the  third  brush  holder  to  the  brush 
ring  is  reached  through  the  opening  in  the  rear  end 
housing,  which  is  to  the  right  of  the  generator  terminal 
when  facing  the  rear  end  of  the  generator.  This  is  a 
hexagonal  nut,  and  a  small  thin  open  end  wrench  is  the 
best  tool  to  use  in  turning  this  nut.  Loosen  this  nut  and 


FIGURE  11. 

LOOKING  AT   BACK   OF   GENERATOR   BRUSH  RING. 

A  is  slot  in  which  the  bolt  C  that  holds  third  brush  holder 
in  place  may  be  moved,  thus  changing  position,  or  ifsetting'J  of 
the  third  brush.  B  are  notches  cut  in  inner  circumference 
of  brush  ring,  through  which  the  screws  whose  heads  are  shown 
at  K  in  Figure  8  pass.  D  .is  the  narrow  ring  which  clamps 
brush  ring  in  place.  D  is  also  shown  at  F  in  Figure  5. 

then  tap  the  third  brush  holder  so  as  to  move  it  in  the 
slot  shown  at  A  in  Figure  11.  Moving  the  third  brush 
in  the  same  direction  as  the  armature  is  rotating  in- 
creates  the  generator  current.  Moving  it  in  the  opposite 
direction  decreases  the  current.  The  engine  should  be 
running  at  about  800  revolutions.  When  the  desired 
value  of  current  is  obtained,  tighten  the  nut.  Then  run 
the  engine  at  different  speeds  so  as  to  be  sure  that  the 

15 


DESCRIPTION  OF  PARTS 

current  does  not  reach  a  value  greater  than  that  indicated 
on  the  ammeter  when  the  nut  was  tightened.  It  is  a  good 
practice  to  sandpaper  the  under  surface  of  the  third  brush 
after  the  brush  has  been  set  in  its  new  position.  Direc- 
tions for  sanding  brushes  are  given  on  page  8. 

GENERATOR  PERFORMANCE.  The  cutout  should 
close  when  the  generator  is  turning  at  a  rate  of  600  rev- 
olutions per  minute,  or  at  car  speed  of  10  miles  per  hour. 
At  this  speed  the  voltage  of  the  generator  should  be  a  lit- 
tle higher  than  the  voltage  of  the  battery,  in  order  that 
the  generator  may  begin  to  deliver  current  to  the  battery 
as  soon  as  the  cutout  closes.  As  the  speed  of  the  engine 
increases,  the  current  will  continue  to  increase  until  the 
generator  is  turning  at  1200  revolutions  per  minute,  or 
until  the  car  is  traveling  at  the  rate  of  20  miles  per  hour 
in  high  speed.  At  this  speed  the  current  reaches  its  max- 
imum value.  At  higher  speeds,  the  charging  current 
gradually  decreases.  This  decrease  is  caused  by  the  arma- 
ture current  twisting  the  magnetic  field  so  that  the  cur- 
rent through  the  field  coils  decreases  as  the  generator 
speed  increases. 

A  charging  current  of  10  amperes  is  the  best  for  aver- 
age driving  conditions.  As  the  speed  of  the  engine  is  de- 
creased below  20  miles  per  hour,  the  current  will  also  de- 
crease, because  the  voltage  of  the  generator  will  decrease. 
The  cutout  will  not  open  and  disconnect  the  generator 
from  the  battery  until  the  voltage  of  the  generator  has 
dropped  slightly  below  that  of  the  battery.  The  battery 
will  then  begin  to  discharge  into  the  generator.  This 
will  be  indicated  by  the  pointer  on  the  ammeter  coming 
down  to  the  "0"  line  on  the  scale  and  then  moving  on 
past  the  "0"  line  for  one  or  two  amperes.  This  discharge 
current  should  not  exceed  several  amperes,  and  should 
flow  for  only  an  instant  before  the  cutout  opens. 

HOW  TO  REMOVE  THE  GENERATOR  FROM  THE 
CAR.  First  remove  the  three  cap  screws  which  fasten  the 

16 


DESCRIPTION  OF  PARTS 


generator  to  the  cylinder  front  end  cover.  Then  place 
the  point  of  a  screw  driver  between  the  generator  and  the 
front  end  cover,  and  gradually  force  off  the  generator. 
Always  start  prying  at  the  top  of  the  generator  and  force 
the  generator  backward  and  downward  at  the  same  time. 
If  it  is  desired  to  run  the  car  while  the  generator  is  re- 
moved, the  time  gear  should  be  covered  with  a  plate  until 
the  generator  is  replaced.  The  plate  may  be  obtained 
from  a  Ford  dealer. 

HOW  TO  TAKE  GENERATOR  APART.  1.  Remove 
the  cover  which  closes  up  the  openings  in  the  rear  end 
housing.  This  is  done  by  taking  out  the  two  screws 
which  hold  it  in  place  as  shown  at  F  in  Figure  1. 

2.  Grasp  the  pigtail  on  each  brush  with  a  pair  of  long 
nosed  pliers  and  pull  the  brush  up  until  the  brush  spring 
snaps  from  the  top  of  the  brush  and  bears  against  the 
side  of  the  brush.    This  will  hold  the  brush  clear  of  the 
commutator. 

3.  Take  out  the  six  flat  head  screws,  shown  at  M  in 
Figure  4.     Then  insert  point  of  screwdriver  between  the 
front  end  cap  and  the  frame  and  pry  the  cap  loose.    Then 
grasp  the  pinion  and  pull  out  the  armature. 

4.  Remove  the  rear  end  housing  by  taking  out  the 
four  screws  shown  at  H  in  Figure  1.     Pry  the  housing 
loose  with  a  screw  driver.    IN  REMOVING  THIS  HOUS- 
ING BE   EXTREMELY    CAREFUL   NOT   TO    DAMAGE 
THE  INSULATION  AROUND  THE  GENERATOR  TER- 
MINAL. 

5.  When  the  rear  end  housing  is  loose  it  may  be  pulled 
back  as  far  as  the  wires  which  are  fastened  to  the  brushes 
will  allow.     To  remove  the  housing  entirely,  disconnect 
the  wires  from  the  brushes,  being  careful  to  note  the  con- 
nections.   Figure  6  shows  the  proper  connections. 

6.  To  remove  the  brush  ring,  take  out  the  four  screws 
shown  at  K  in  Figure  8.     The  main  brush  holders  are 
riveted  to  the  ring  and  cannot  be  removed  from  the  ring. 

17 


DESCRIPTION"  OF  PARTS 


2.     STARTING  MOTOR. 

LOCATION  AND  MOUNTING.  The  starting  motor  is 
located  on  the  left  side  of  the  engine  at  the  rear  end,  as 
shown  at  A  in  Figure  21.  It  is  fastened  to  the  transmis- 
sion cover  by  four  5/16  inch  bolts. 


FIGURE  12. 

LOOKING  AT  FRONT   END   OF   STARTING  MOTOR. 
A  is  motor  terminal.     G  are  two  of  the  screws  which  hold 
rear  end  housing  in  place.    E  is  front  end  cap.    F  are  screws 
which  hold  front  end  cap  in  place. 

DRIVE.  The  well  known  Bendix  drive  system  is  used. 
This  system  is  used  so  extensively  on  automobiles  that  no 
description  is  needed  here.  The  motor  pinion  has  10 
teeth,  and  engages  with  a  gear  of  120  teeth  cut  on  the 
circumference  of  the  flywheel.  The  motor  therefore  turns 
twelve  times  as  fast  as  the  engine. 

LUBRICATION.    The  motor  has  plain  bearings  without 

18 


DESCRIPTION  OF  PARTS 

balls.  The  motor  is  used  very  little  and  therefore  does 
not  require  much  lubrication.  The  bearing  next  to  the 
flywheel  is  lubricated  by  splash  from  the  flywheel.  The 
other  motor  bearing  is  not  lubricated. 

The  front  bearing  has  a  brass  or  bronze  bushing,  and 
the  rear  bearing  has  a  bushing  of  soft  bearing  metal. 


FIGURE  13. 

LOOKING  AT  INSIDE  OF  MOTOR  REAR  END  HOUSING. 
A  are  the  brushes.  B  are  the  grounded  brush  holders.  BG 
are  the  insulated  brush  holders.  C  are  the  bare  copper  pig- 
tails which  connect  brushes  to  brush  holders.  D  are  the  brush 
springs.  E  is  the  brush  ring. 

FRAME.  The  frame,  pole  pieces,  rear  end  housing,  and 
rear  end  housing  cover  are  all  of  the  same  material  and 
dimensions  as  those  of  the  generator,  as  already  de- 
scribed. The  cap  on  the  drive  end  of  the  motor  is  dif- 

19 


DESCRIPTION  OF  PARTS 


ferent.  Its  shape  and  construction  are  shown  at  E  in 
Figure  12.  It  is  fastened  to  the  end  of  the  frame  by  six 
screws  shown  at  F  in  Figure  12. 


FIGURE  14. 

LOOKING  AT  FRONT  END  OF  MOTOR  FRAME. 
A  is  the  motor  terminal.  B  is  the  insulation  around  the 
motor  terminal.  C  is  lower  end  of  motor  terminal.  D  are 
the  joints  between  the  field  coils.  E  are  leads  connecting  field 
coils  to  brushes  shown  at  BG  in  Figure  13.  F  are  the  field 
pole  pieces. 

BRUSHES.  The  motor  has  four  copper  composition 
brushes  arranged  as  shown  in  Figure  13.  Each  brush  has 
two  heavy  bare  copper  pigtails,  the  free  ends  of  which 
are  soldered  into  flat  copper  terminals  that  are  fastened 
to  the  brush  holder  by  a  round  head  machine  screw.  The 


DESCRIPTION  OF  PARTS 


brushes  are  each  3/4  inch  long,  3/8  inch  wide,  and 
3/4  inch  high. 

The  brush  holders  are  made  of  aluminum,  and  are 
riveted  to  the  brush  ring.  The  two  brushes  shown  at 
BG-  in  Figure  13  are  insulated  from  the  brush  ring  by 
fiber  strips.  These  brushes  are  connected  to  one  end  of 
the  field  coils.  The  brushes  shown  at  B  in  Figure  13  are 
riveted  directly  to  the  metal  of  the  brush  ring,  and  are 
therefore  the  "grounded"  brushes.  They  have  no  wires 
except  the  pigtails  from  the  brushes  attached  to  them. 

The  motor  brush  springs  are  similar  to  those  in  the 


LOOKING   AT  INSIDE  OF  END  CAP 


FIGURE  15. 
MOTOR  BRUSHES  AND  FIELD  COILS. 

generator.  Each  spring  is  made  of  coiled  flat  spring  steel, 
one  end  bearing  on  the  top  of  the  brush,  and  the  other 
end  being  fastened  in  a  slotted  stud  which  is  mounted  di- 
rectly on  the  brush  holder. 

The  brush  ring  is  riveted  to  the  housing  with  four 
rivets  and  therefore  cannot  be  removed  or  shifted. 

The  remarks  made  about  taking  care  of  the  generator 
brushes  apply  to  the  motor  brushes  also. 

FIELD  WINDINGS.  Each  of  the  four  motor  field  poles 
carries  one  heavy  coil,  as  shown  in  Figure  14.  The  con- 

21 


DESCRIPTION  OF  PARTS 

nections  of  these  coils  are  shown  in  Figure  15.  The  joints 
between  field  coils  (shown  at  D.  Figure  14)  are  not 
covered  with  any  insulating  material,  and  care  should 
be  taken  that  the  bare  copper  does  not  touch  the  motor 
frame,  as  this  would  practically  short  circuit  the  bat- 
tery when  the  starting  switch  is  closed. 

ARMATURE.  The  motor  armature  (shown  in  Figure 
16)  has  21  slots  and  21  commutator  segments.  The  wind- 
ing is  made  up  of  heavy  flat  copper,  the  top  layer  being 
insulated  merely  with  an  insulating  lacquer  or  varnish. 


v  FIGURE  16. 

MOTOR  ARMATURE. 

The  conductors  in  the  bottom  layer  are  insulated  with  a 
cloth.1  tape. 

As  to  the  care  of  the  commutator,  the  remarks  already 
made  about  the  care  of  the  generator  commutator  apply 
to  the  motor  commutator  also. 

PERFORMANCE.  The  duty  of  the  starting  motor  is 
simply  to  turn  over,  or  crank  the  engine  in  order  to  start 
the  engine.  This  it  does  by  the  Bendix  pinion  on  the  mo- 
tor shaft  meshing  automatically  with  the  gear  teeth  cut 
on  the  rim  of  the  flywheel.  When  the  engine  starts  and 

22 


DESCRIPTION  OF  PARTS 


runs  under  its  own  power,  the  Bendix  pinion  is  automat- 
ically driven  out  of  mesh  with  the  flywheel  gear.  As 
already  stated,  the  motor  turns  at  12  times  the  speed  of 
the  engine,  there  being  10  teeth  on  the  Bendix  pinion 
and  120  on  the  flywheel  gear. 

The  results  of  some  tests  are  given  below: 

(a)  Motor  takes  70  to  80  amperes  when  running  with- 
out load. 

(b)  Motor  takes  140  to  200  amperes  when  cranking 
a  loose  engine. 

(c)  Motor  takes  225  to  300  amperes  when  cranking  a 
stiff  engine. 

(d)  Motor  takes  300  amperes  when  blocked  and  not 
permitted  to  turn. 

(e)  Running  without  load,  motor  consumes  373  watts, 
or  1/2  H.  P.    The  current  was  65  amperes  at  5.75  volts. 

(f)  Tests  on  a  typical  new  engine:     Motor  turning 
at  900  R.  P.  M.  engine  at  75  R.  P.  M.    Motor  taking  275- 
300  amperes  at  4.5  volts,  giving  a  maximum  power  con- 
sumption of  1350  watts,  or  1.8  H.  P. 

(g)  Tests  on  a  typical  run-in  engine:    Motor  turning 
at  2200  R.  P.  M.,  engine  turning  at  183.3  R.  P.  M.    Mo- 
tor taking  140  amperes  at  5  volts,  giving  700  watts,  or 
0.93  H.  P. 

HOW  TO  REMOVE  MOTOR  FROM  THE  CAR:  (a) 

Remove  engine  pan  on  left  hand  side  of  engine. 

(b)  With  a  screw  driver  remove  the  four  small  screws 
which  hold  the  shaft  cover  to  the  transmission  cover,  in 
back  of  the  flywheel. 

(c)  After   this    cover   is   removed,    turn   the   Bendix 
drive  shaft  around  so  that  the  set  screw  on  the  end  of  this 
shaft  is  in  a  horizontal  position  with  the  head  pointing 
toward  the  left,  as  you  face  the  rear  of  the  flywheel.    Un- 
der this  set  screw  is  a  split  spring  lock  washer  having 
sharp  points  or  spurs  at  the  joint  between  the  two  halves 
on  opposite  sides  of  the  washer.     One  of  these  spurs  is 

23 


DESCRIPTION  OF  PARTS 

turned  against  the  Bendix  collar  and  the  other  is  turned 
up  against  the  screw  head.  Bend  back  the  spur  which 
has  been  forced  against  the  screw,  and  remove  the  set 
screw.  The  lock  washer  may  be  broken  in  doing  this,  and 
a  new  one  should  be  used  when  the  motor  is  again  made 
ready  for  cranking. 

(d)  Next    pull    out   the    Bendix   pinion,    spring   and 
sleeve. 

(e)  Remove   the   four   screws   that  hold   the   starter 
housing  to  the  transmission  cover,  and  pull  out  the  mo- 
tor,  taking  it   down  through  the   chassis;   through  the 
opening  made  when  the  engine  pan  was  removed. 

(f )  When  you  replace  the  starting  motor,  be  sure  that 
the  terminal  mounted  near  the  rear  end  of  frame  is  on 
top. 

(g)  If  the  car  is  to  be  used  while  the  starting  motor 
is  removed,  put  the  transmission  cover  plates  in  place. 
If  these  are  not  at  hand  they  may  be  obtained  from  a 
Ford  dealer. 

HOW  TO  TAKE  MOTOR  APART.  Having  taken  off 
the  Bendix  drive  mechanism,  take  the  starting  motor 
apart  as  follows: 

(a)  Remove  the  cover  from  the  rear  end  housing  by 
taking  out  the  screws  shown  at  C  in  Figure  2,  and  forcing 
the  cover  off  with  a  screw  driver. 

(b)  Grasp  a  pigtail  of  each  brush  with  a  pair  of  long 
nose  pliers  and  pull  up  until  the  brush  spring  snaps  off 
the  top  of  the  brush  and  bears  against  the  side  of  the 
brush.     This  will  hold  the  brushes  clear  of  the  commu- 
tator. 

(c)  Take  out  the  six  screws  in  the  drive  end  cap, 
shown  at  F  in  Figure  12.     Pry  the  end  cap  off  with  a 
screw  driver. 

(d)  Pull  out  the  armature. 

(e)  Remove  the  four  screws  shown  at  C  in  Figure 

24 


DESCRIPTION  OF  PARTS 

12,  which  hold  the  rear  end  housing  in  place.     Pry  off 
this  housing  with  a  screw  driver. 

(f)  Disconnect  the   two  leads  from  the  ungrounded 
brush  holder. 

(g)  Brushes  may  be  removed  by  unscrewing  the  cop- 
per pigtails  and  then  lifting  brushes  out.     Brush  holders 
cannot  be  removed. 

3.     THE  BATTERY. 

TYPE.  The  battery  is  an  Exide,  6  volt,  13  plate  bat- 
tery, type  3-XC-13-1. 

LOCATION.  On  earlier  cars  the  battery  was  mounted 
on  the  left  running  board.  In  later  cars  the  battery  is 
under  the  left  rear  floor  boards. 

MOUNTING.  The  battery  when  placed  under  the  floor 
boards  is  carried  in  a  frame  made  of  flat  iron  bars.  It  is 
held  down  by  two  flat  pieces  which  press  down  on  the  top 
of  the  box  at  the  ends.  These  pieces  are  held  in  place  by 
two  thumb  screws.  Battery  may  be  removed  by  remov- 
ing the  thumb  screws  and  lifting  out  the  two  flat  pieces. 
The  floor  boards  must  be  lifted  up  in  order  to  expose  the 
battery.  In  the  Coupe,  there  is  a  removable  section  of 
floor  boards  just  beside  the  gas  tank  in  the  rear  compart- 
ment. In  the  Sedan  the  removable  section  of  floor  boards 
is  in  front  of  the  rear  seat. 

MAINTENANCE,  CARE  AND  REPAIR  OF  BATTERY. 
This  is  a  subject  which  requires  special  and  complete 
treatment.  The  book  "The  Automobile  Storage  Battery, 
Its  Care  and  Repair,"  published  by  the  American  Bureau 
of  Engineering,  Inc.,  covers  the  subject  of  the  storage 
battery  completely  from  the  repairman's  point  of  view. 

4.     CUTOUT. 

LOCATION.  On  many  cars  the  cutout  is  mounted  un- 
der the  engine  hood  at  the  right  side  of  the  dash  board. 

25 


DESCRIPTION  OF  PARTS 


The  base  of  the  cutout  is  then  grounded  to  an  iron  arm 
projecting  upward  from  the  frame  of  the  car.  On  other 
cars  the  cutout  is  mounted  on  top  of  the  generator  frame, 
and  its  frame  is  then  grounded  directly  to  the  generator 
frame. 

CUTOUT  ON  DASH.  There  are  three  terminals  on  the 
base  of  the  cutout,  as  shown  in  Figure  24.  The  two  out- 
side terminals  are  marked  "Gen."  and  "Bat.",  respectively. 
The  one  marked  "Gen."  is  connected  to  the  generator 
terminal,  and  the  one  marked  "Bat."  is  connected  to  the 
ammeter.  The  two  outside  terminals  are  insulated  from 
the  base  of  the  cutout,  while  the  middle  one,  which  is 
not  marked,  is  grounded  to  the  base. 

The  movable  arm  carries  one  of  the  contact  points.  A 
flat  spring  at  one  end  tends  to  hold  the  two  contact  points 
apart.  Passing  through  an  opening  in  this  arm  near  the 
contact  point  is  a  bent  over  brass  piece.  By  bending  or 
straightening  this  piece,  the  distance  between  the  two 
contact  points  may  be  varied.  The  correct  distance  is 
about  1/32  inch. 

The  stationary  contact  point  is  carried  on  an  arm  which 
is  insulated  from  the  upright  piece  on  which  it  is 
mounted.  The  distance  between  the  points  may  also  be 
changed  by  moving  this  arm  up  or  down. 

CUTOUT  ON  GENERATOR.  Figure  24B  shows  the  in- 
ternal connections  of  the  cutout  which  is  mounted  di- 
rectly on  top  of  the  generator  frame.  The  piece  marked 
"T"  is  bolted  to  the  generator  terminal.  Piece  T  is  con- 
nected to  part  H  by  a  round  head  machine  screw  which 
may  be  seen  by  looking  at  the  bottom  of  the  cutout.  T 
and  H  are  both  insulated  from  the  base  of  the  cutout 
which  is  fastened  to  the  generator  frame.  The  arm  E  is 
mounted  on,  and  is  in  electrical  connection  with  H.  At 
one  end  of  arm  E  is  one  of  the  contact  points  as  shown. 
The  other  contact  point  is  fastened  to  piece  D,  which  is  in- 
sulated from  H  and  E.  A  brass  hook,  L,  which  is  an  ex- 

26 


DESCRIPTION  OF  PARTS 


tension  of  piece  D,  acts  as  a  stop  for  the  arm  E.  The  end 
of  this  hook  touches  a  small  disc  of  insulation  on  the 
arm  E,  as  shown  in  the  diagram.  By  bending  the  hook, 
the  air-gap  between  the  cutout  points  (when  engine  is 
not  running)  may  be  changed  so  as  to  secure  proper  op- 
eration of  the  cutout  in  closing.  A  spring,  S,  tends  to 
hold  the  contact  points  away  from  each  other.  By  bend- 
ing this  spring  its  tension  may  be  increased  or  decreased, 
to  secure  proper  action  of  the  cutout  both  in  closing  and 
opening  the  circuit  between  the  generator  and  the  bat- 
tery. Directions  for  adjusting  the  cutout  action  are 
given  on  page  29. 

PATH  OF  CURRENT  THROUGH  CUTOUT.  Current 
from  the  generator  enters  the  cutout  at  T,  goes  through  T 
into  parts  H  and  E,  thence  through  the  two  contact  mak- 
ing points  into  part  D,  thence  through  the  current  coil 
(the  outside  one,  which  is  made  of  the  heavy  wire)  into 
piece  C  (which  is  insulated  from  all  parts  except  the  cur- 
rent coil),  then  through  a  screw  A  (which  passes  through 
the  cutout  cover,  but  is  insulated  from  the  cover)  into  the 
insulated  plate,  as  shown  in  Figure  24A,  and  thence  to 
the  battery  along  the  wire  fastened  to  this  plate  under 
the  screw  which  is  marked  "B"  in  the  diagram  and  also 
on  the  cutout. 

Screw  A  is  sealed  to  the  cover,  and  should  always  be 
turned  down  tight,  since  the  charging  circuit  is  broken  if 
this  screw  is  taken  out.  Screw  A  must,  of  course,  be  re- 
moved if  it  is  desired  to  take  off  the  cutout  cover. 

The  base  of  the  cutout,  which  is  screwed  down  to  the 
generator  frame,  is  connected  to  one  end  of  the  voltage 
coil,  but  is  insulated  from  all  other  parts  except  the  cover 
which  fits  over  it.  The  other  end  of  the  voltage  coil  is 
connected  to  piece  H. 

The  circuit  for  the  voltage  coil  is:  From  the  un- 
grounded main  generator  brush  to  the  generator  ter- 
minal, through  piece  T  to  part  H,  through  the  voltage  coil 
to  the  base  I,  through  the  generator  frame,  thenoe 

27 


DESCRIPTION  OF  PARTS 

through  the  grounded  main  generator  brush  and  back  to 
the  armature. 

INSTRUCTIONS  APPLYING  TO  BOTH  CUTOUTS. 

The  contact  points  should  at  all  times  be  clean  and 
smooth,  and  when  they  are  touching  each  other  they 
should  be  making  contact  at  all  points  of  their  surfaces. 
They  may  be  cleaned  by  drawing  between  them  a  rag 
moistened  with  gasoline,  while  pressing  down  on  the 
movable  contact.  To  make  them  smooth,  or  to  improve 
the  contact,  a  piece  of  fine  emery  cloth,  or  a  very  fine  file 
may  be  used,  drawing  the  emery  cloth  or  file  between  the 
contacts  while  pressing  down  on  the  movable  contact. 

The  movable  arm  which  carries  one  of  the  contact 
points  is  insulated  from  the  base  of  the  cutout,  and  care 
must  be  taken  that  it  does  not  become  grounded  to  the 
base. 

In  prying  off  the  cover  of  the  cutout,  be  careful  to 
bring  it  up  straight,  so  as  not  to  touch  either  contact 
point  with  the  cover,  as  this  will  ground  the  battery  if 
the  cover  is  touching  the  base  also. 

ACTION.  The  purpose  of  the  cutout  is:  (1)  To  con- 
nect the  generator  to  the  battery  automatically  as  soon 
as  the  voltage  of  the  generator  is  slightly  higher  than 
that  of  the  battery.  (2)  To  disconnect  the  generator 
from  the  battery  automatically,  as  soon  as  the  voltage  of 
the  generator  falls  below  that  of  the  battery. 

THE  CUTOUT  PERFORMS  NO  OTHER  DUTIES  THAN 
THESE.  It  does  not  protect  the  battery  from  being 
overcharged.  To  accomplish  the  automatic  action  of  the 
cutout  in  connecting  the  generator  to,  and  disconnecting 
it  from  the  battery,  two  windings  are  placed  upon  the 
cutout.  One  is  made  of  heavy  wire  and  carries  all  the 
current  delivered  by  the  generator.  The  other  is  made 
of  a  small  wire,  and  is  connected  so  as  to  receive  the  full, 


DESCRIPTION  OF  PARTS 

generator  voltage  across  it.  The  small  wire  or  voltage 
coil  performs  the  duty  of  closing  the  contact  points  when 
the  generator  voltage  is  slightly  greater  than  that  of  the 
battery.  As  soon  as  the  contact  points  close,  current  flows 
through  the  heavy  wire  winding.  As  long  as  the  gen- 
erator is  charging  the  battery,  the  magnetic  eifects  of 
both  coils  act  in  the  same  direction,  and  have  a  tendency 
to  hold  the  contact  points  closed  tight.  When  the  voltage 
of  the  generator  falls  below  that  of  the  battery,  the  bat- 
tery begins  to  discharge  into  the  generator,  and  there- 
fore the  current  through  the  heavy  wire  coil  of  the  cut- 
out is  reversed.  The  current  in  the  shunt  coil  does  not 
reverse  its  direction.  The  magnetic  effect  of  the  small 
wire  coil  and  the  heavy  wire  coil  are  then  opposed  to  one 
another,  and  this  causes  the  cutout  core  to  lose  its  at- 
traction for  the  movable  arm,  and  hence  the  points  sep- 
arate and  open  the  circuit  between  the  generator  and  the 
battery. 

ADJUSTMENT.  To  properly  adjust  the  cutout,  con- 
nect an  ammeter  in  series  with  the  generator  as  shown 
in  Figure  10.  Be  sure  that  the  generator  is  delivering 
current  of  about  10  amperes.  The  specific  gravity  of 
each  cell  of  the  battery  should  not  be  less  than  1.250. 
Turn  off  all  the  lamps  and  run  the  engine  on  the  mag- 
neto. With  the  engine  running,  gradually  close  the 
throttle  until  the  engine  runs  so  slowly  that  the  cutout 
points  open,  or  separate.  The  points  may  be  watched  to 
determine  when  they  have  separated,  or  else  the  pointer 
on  your  ammeter  may  be  observed.  The  pointer  will 
swing  past  the  "0"  line  on  the  ammeter  scale  for  an  in- 
stant just  before  the  cutout  opens  and  will  then  come 
back  to  and  remain  stationary  over  the  "0"  line. 

Now  gradually  increase  the  speed  of  the  engine,  while 
carefully  watching  your  ammeter  pointer.  When  the 
generator  is  running  at  600  R.  P.  M.,  or  the  engine  is 
running  at  a  speed  that  would  give  a  speed  of  10  miles 
per  hour  on  the  road,  the  cutout  points  should  close. 
There  should  be  a  sligfy  movement  of  the  ammeter 

"39 


DESCRIPTION  OP  PARTS 

pointer  when  the  cutout  closes,  indicating-  a  charge  of  2 
or  3  amperes.  With  a  further  increase  of  speed,  the 
ammeter  pointer  should  swing  across  the  scale  until  it  is 
indicating  a  charge  of  10  amperes.  This  should  be  the 
maximum  charge. 

If,  when  the  cutout  closes,  your  ammeter  pointer  reads 
reversed,  and  thus  indicates  that  the  battery  starts  to 
discharge  into  the  generator,  the  cutout  is  closing  before 
the  voltage  of  the  generator  is  equal  to  that  of  the  bat- 
tery. This  should  be  remedied  by  bending  the  spring  on 
the  movable  arm  of  the  cutout  so  as  to  make  the  spring 
hold  this  arm  up  with  greater  force,  requiring  a  higher 
generator  voltage  to  close  the  cutout.  Another  way  is  to 
increase  the  distance  between  the  points  by  straightening 
the  bent  over  piece  or  hook  in  the  arm  a  little. 

If,  when  the  cutout  closes,  your  ammeter  pointer  does 
not  move,  it  indicates  that  the  generator  and  battery  vol- 
tages are  equal  at  that  instant.  The  spring  on  the 
movable  arm  should  be  made  stiffer  by  bending,  or  the 
distance  between  the  points  should  be  increased  as  already 
described. 

If,  when  the  cutout  closes,  your  ammeter  pointer  in- 
dicates the  full  charging  current  of  10  amperes,  the  cut- 
out does  not  close  soon  enough.  To  remedy  this,  weaken 
the  spring  on  the  movable  arm,  or  decrease  the  distance 
between  the  points. 

The  cutout  is  closing  at  the  proper  instant  if  the  am- 
meter pointer  indicates  a  charge  of  not  more  than  two  or 
three  amperes  at  the  instant  the  points  close. 

To  check  the  action  of  the  cutout  in  disconnecting  the 
generator  from  the  battery,  decrease  the  speed  of  the  en- 
gine gradually  and  watch  the  ammeter  pointer.  The 
pointer  will  move  down  toward  the  "0"  line  and  will 
swing  down  past  it  a  slight  distance  before  the  cutout 
opens.  The  distance  which  the  ammeter  pointer  swings 
below  the  "0"  line  should  be  such  as  to  indicate  a  dis- 
charge current  of  not  more  than  two  amperes  or  so  before 
the  points  open,  and  the  pointer  should  be  below  the  "0" 

30 


DESCRIPTION  OF  PARTS 

line  for  an  instant  only.  Should  the  pointer  indicate  a  dis- 
charge of  more  than  three  amperes,  or  should  it  remain 
below  the  "0"  line  for  more  than  an  instant,  the  points 
are  not  opening  soon  enough,  and  the  spring  on  the  mova- 
ble arm  should  be  strengthened. 

After  making  any  adjustment  on  the  cutout,  be  sure 
to  check  its  action  to  be  sure  that  it  is  then  working  as 
it  should. 

5.     FORD  AMMETER. 

LOCATION.  The  ammeter  is  mounted  on  the  instru- 
ment panel  in  front  of  the  driver,  and  to  the  right  of  the 
combined  lighting  and  ignition  switch. 

PURPOSE.  The  ammeter  is  connected  so  that  it  will 
indicate  the  current  flowing  in  or  out  of  the  battery,  ex- 
cept that  it  does  not  indicate  or  measure  the  starting  cur- 
rent. 

WHEN  THE  ENGINE  IS  NOT  RUNNING,  AND  THE 
LAMPS  ARE  ALL  TURNED  OFF,  the  ammeter  pointer 
should  be  over  the  "0"  line  on  the  scale,  indicating  that 
the  battery  is  neither  charging  nor  discharging.  Should 
the  pointer  under  these  conditions  indicate  that  the  bat- 
tery is  discharging,  by  moving  to  the  part  of  the  scale 
which  is  marked  "Discharge,"  there  is  some  trouble  in 
the  electrical  system  which  should  be  located  immedi- 
ately, to  prevent  the  battery  from  running  down.  Such 
troubles  are  described  in  Chart  1,  beginning  on  page  53. 

WHEN  THE  LAMPS  ARE  TURNED  ON  and  the  en- 
gine is  not  running,  the  ammeter  pointer  should  move 
over  to  the  part  of  the  scale  marked  "Discharge,"  indi- 
cating that  the  battery  is  furnishing  the  current  to  op- 
erate the  lights. 

WHEN  THE  ENGINE  IS  RUNNING,  AND  THE 

31 


DESCRIPTION  OF  PARTS 


LAMPS  ARE  TURNED  OFF,  the  ammeter  pointer  should 
move  to  the  part  of  the  scale  which  is  marked  "Charge," 
showing  that  the  generator  is  charging  the  battery.  The 
pointer  should  indicate  a  charge  of  about  10  amperes. 
If  the  pointer  does  not  move  from  the  "0"  line  when  the 
engine  is  running,  it  indicates  that  the  battery  is  not  re- 
ceiving a  charging  current.  Troubles  that  cause  this  con- 
dition are  taken  care  of  in  Chart  7,  beginning  on  page 
77,  and  Chart  9,  beginning  on  page  87. 

A  good  way  to  test  the  ammeter  is  to  turn  on  the  lights 
when  the  engine  is  not  running.  If  the  pointer  does  not 
move  from  the  "0"  line,  the  ammeter  is  defective.  Shoull 
the  pointer  move  to  the  part  of  the  scale  which  is  markei 
"charge,"  under  these  conditions,  the  connections  on  the 
studs  in  the  back  of  the  ammeter  should  be  interchanged. 

6.     LIGHTING  AND  IGNITION  SWITCH. 

Several  types  of  switches  have  been  used.  On  some 
early  models  there  were  several  separate  push  and  pull 
buttons  on  the  dash  for  controlling  the  lamps.  On  some- 
what later  models  the  round  type  switch  shown  in  Figure 
17  was  used.  On  still  later  models  the  round  type  switch 
shown  in  Figure  18  was  used.  Each  of  these  round  type 
switches  have  a  handle  extending  downward  from  the 
center  of  the  switch  for  controlling  the  lamps.  The  ig- 
nition is  switched  on  or  off,  and  to  the  battery  or  the 
magneto  by  a  key  inserted  in  a  key  hole  in  the  center  of 
the  switch. 

In  the  early  type  of  round  switch,  several  troubles  have 
been  found,  due  to  short  circuiting  between  the  various 
terminals.  This  was  done  by  the  wires  which  are  con- 
nected to  the  terminals  on  the 'back  of  the  switch  (shown 
in  Figure  24)  or  by  trouble  inside  the  switch.  The 
troubles  which  have  been  found  consist  of  the  following: 

(a)  "$OIL"  TERMINAL  SHORT-CIRCUITED  WITH 
"BAT"  TERMINAL.  This  trouble  makes  it  impossible  to 

32 


DESCRIPTION  OF  PARTS 


y///A  \$$$$s&    fc^ssss 

3  V//A 

s~ 

7 

ROtfJMD 


LIGHTING  8c  IGNITION  SW.  EARLY  TYPE 

FIGURE  17. 


33 


DESCRIPTION  OF  PARTS 


turn  off  the  ignition,  and  the  engine  continues  to  run 
after  the  ignition  key  is  turned  to  "Off."  If  the  ignition 
key  is  turned  to  the  "Mag"  position  while  this  short  cir- 


TAIL_ 


MAQ. 


AUX. 


COlt- 


L.ARSE    DISC 
FOR   L-I6HTS 
.SMAUL-  DISC 
FOR  IGNITION 


AROUND 


HHAD 


BAT 


VIEW  THRU     "A- A 

LJ6HTINS  8c    I6NITION    SWITCH 

L.ATER    TVPE 
FIGURE  18. 

cuit  exists,  the  battery  will  discharge  into  the  magneto 
at  a  rate  of  about  18-20  amps  while  engine  is  not  run- 
ning, 

34 


DESCRIPTION  OF  PARTS 


(b)  "HEAD"  TERMINAL  SHORT-CIRCUITED  WITH 
THE  "COIL"  TERMINAL.    If  the  ignition  key  is  turned 
to  the  "Mag"  position,  when  engine  is  running,  the  lamps 
burn  out.    Using  the  battery  for  ignition  with  this  short 
circuit  present,  makes  head  lamps  burn  even  if  the  light- 
ing switch  is  turned  off. 

(c)  IF  "MAG"  TERMINAL  SHORT  CIRCUITS  WITH 
THE  "DIM"  terminal,  the  small  bulbs  in  the  head  lamps 
will  burn  out. 

With  the  later  type  of  round  switch,  these  short  cir- 
cuits do  not  occur. 

The  later  type  of  switch  has  two  movable  round  discs, 
one  for  the  ignition,  and  one  for  the  lights. 

When  the  ignition  key  is  turned  to  the  "Bat"  posi- 
tion marked  on  the  front  of  the  switch,  the  battery  will 
be  furnishing  the  ignition  current  when  starting.  When 
running,  the  generator  will  be  furnishing  the  ignition 
current.  With  the  ignition  key  turned  to  the  "Mag"  po- 
sition, the  Ford  magneto  is  furnishing  the  ignition  cur- 
rent. 

If  the  handle  controlling  the  lights  is  turned  to  the 
"Dim"  or  "Aux."  position,  the  tail  lamp,  and  the  small 
bulbs  in  the  headlights  will  burn.  With  the  handle 
turned  to  the  "On"  position,  the  tail  lamp  and  large  bulb 
in  the  headlights  will  burn. 

If  any  of  the  short  circuit  troubles  listed  above  occur, 
the  entire  panel  on  which  the  ammeter  and  switch  are 
mounted  may  be  removed  by  taking  out  the  four  screws 
in  the  corners  of  the  panel.  The  wires  attached  to  the 
back  of  the  switch  should  be  inspected  carefully  to  make 
sure  that  they  are  not  causing  the  trouble.  The  entire 
rear  cover  may  be  removed  from  the  switch  in  order  to 
look  for  internal  short  circuits. 

7.     STARTING  SWITCH. 

LOCATION.  Under  the  floor  boards  in  front  of  the 
driver. 

35 


DESCRIPTION  OF  PARTS 

PURPOSE.  The  only  duty  of  the  starting  switch  is  to 
connect  the  starting  motor  to  the  battery  when  it  is  de- 
sired to  have  the  motor  crank  the  engine.  The  switch  is 
closed  by  pushing  down  on  it  with  the  foot.  The  switch 
plunger  is  held  in  the  open  position  by  a  spring,  which 
opens  the  switch  when  the  foot  is  removed  from  the  top 
of  the  plunger.  The  plunger  is  insulated  from  the  switch. 
Should  this  insulation  become  defective  the  battery  will 
be  short-circuited  when  the  plunger  is  pushed  down.  This 
will  run  the  battery  down  and  burn  the  switch  contacts. 

CONSTRUCTION.  The  starting  switch  housing  is  in 
two  parts  held  together  by  two  flat  head  screws.  The  top 
part  contains  the  plunger  and  the  lower  part  contains  two 
contact  plates.  Be  sure  to  keep  the  space  between  the 
contact  plates  in  the  lower  part  of  the  switch  free  from 
dirt  of  any  kind. 

Any  burning  or  pitting  caused  by  arcing  when  the 
starting  circuit  is  opened  or  closed  should  be  removed 
with  sandpaper  or  emery  cloth. 

The  starting  cables  are  fastened  to  terminals  on  the 
lower  part  of  the  switch.  It  is  essential  that  all  terminal 
connections  in  the  starting  circuit  should  be  perfectly 
clean  and  tight,  because  a  loose  connection  might  cause 
such  a  drop  of  voltage  when  cranking  the  engine  with 
the  motor  that  the  motor  will  not  crank  the  engine  fast 
enough. 

8.     LAMPS. 

In  the  headlights  are  two  National  Mazda  6-8  volt,  17 
candle  power  lamps,  and  two  6-8  volts,  2  candle  power 
lamps.  The  tail  lamp  is  a  6-8  volt,  2  candle  power  lamp 
also. 

9.     WIRING. 

The  wiring  is  shown  clearly  in  Figures  19,  20  and  21. 
From  the  battery  a  heavy  cable  leads  to  the  starting 
switch,  A  second  heavy  cable  leads  from  the  starting 
switch  to  the  starting  motor.  At  the  right  hand  side  of 
the  dash  under  the  engine' hood,  as  you  face  the  dash,  is 

36 


TAIL-  L.AMP 


LIGHTING 
8clGMlTION 
SWITCH 
BACK  VIEW 


STAF?TIN(3   MOTOR 
FRAME  OF  MOTOR 
GROUNDED  TO  CAR.   FRAME 


HU.L-AMP 


FIGURE  19. 
37 


HD.  L.AMP 


TAIL-  LAMP 


ISM.  COIL    , 


FRAME  OF  PYN. 
GROUNDED  TO  CAI?  FPAME 


HD.  L.AMP 


MD.  L.AMP 


38 


HP.  LAMP 


HD.  L.AMP 


ETER 


TAIL.  L.AMP 


FIGURE  19b. 
39 


DESCRIPTION  OF  PARTS 


FIGURE  20. 

FA  INSTALLATION  ON  FORD  CAR. 

B  is  the  terminal  block,  E  is  cable  carrying  ignition  wires 
leading  from  the  low  tension,  or  primary  terminals,  P,  on  the 
ignition  coils  to  the  commutator.  It  also  carries  two  wires 
for  the  right  headlamps.  H  is  wire  leading  from  generator 
to  cutout  terminal  marked  "Geri',  and  from  cutout  terminal 
marked  "Bat"  to  the  Ford  ammeter  on  the  instrument  panel 
in  front  of  the  driver.  K  is  the  cutout.  This  may  also  be 
mounted  directly  on  top  of  the  generator.  N-is  the  generator. 

40 


DESCRIPTION  OF  PARTS 


•8  are  terminals  connected  to  one  end  of  the  high  tension 
winding  of  each  Ford  Ignition  Coil. 

a  multiple  conductor  cable,  shown  at  C  in  Figure  21, 
(which  consists  simply  of  five  insulated  wires  covered  with 
one  braid.  These  wires  in  this  cable  are  connected  to  the 
starting  switch,  tail  light,  Ford  magneto,  left  headlight 
and  the  terminal  board  at  the  right  side  of  the  dash  under 
the  engine  hood  as  you  look  at  the  dash  from  the  front  of 
the  car.  The  wires  have  diiferent  colored  insulations  as 
shown  in  Figure  19.  The  purpose  of  this  is  to  enable  one 
'to  trace  the  circuits  by  means  of  the  colors. 

The  terminal  board  (shown  at  B  in  Figure  21)  carries 
five  terminals  to  which  are  connected  the  wires  from  the 
jcable  mentioned  in  the  preceding  paragraph,  and  the 
[wires  from  a  second  cable  (shown  at  D  in  Figure  21) 
which  leads  to  the  ammeter  and  combined  lighting  and 
ignition  switch. 

Near  the  center  of  the  dash  are  the  terminals  of  the 
[four  ignition  coils,  there  being  one  coil  for  each  engine 
cylinder.    The  lower  set  of  terminals  (shown  at  S  in  Fig- 
iures  20  and  21)  are  connected  to  the  high  tension  wind- 
ings of  the  coils  and  have  cables  attached  to  them  which 
lead  to  the  spark  plugs.    The  upper  row  of  terminals 
(shown  at  P  in  Figures  20  and  21)  are  connected  to  the 
low  tension  windings  of  the  ignition  coils.     Attached  to 
the  upper  terminals  are  wires  with  colored  insulations 
that  go  into  a  cable  (shown  at  E  in  Figure  20)  which 
leads  down  and  forward  to  the  ignition  commutator  and 
the  right  head  lamp.     The  cables  are  all  covered  with  a 
cloth  braid  insulation,  no  metallic  conduits  or  coverings 
of  any  kind  being  used. 

CIRCUITS. 

1.  STARTING  CIRCUIT.  From  the  positive  (+)  bat- 
tery terminal  to  the  starting  switch,  to  the  terminal  on 
top  of  the  starting  motor,  through  the  motor  field  coils, 

41 


DESCRIPTION  OF  PARTS 


FIGURE  21. 

FA   INSTALLATION  ON  FORD  CAR. 

A  is  the  Starting  Motor.  B  is  the  terminal  block.  C  is 
cable  containing  wires  leading  from  terminal  block  to  Ford 
magneto,  tail  lamp,  left  hand  lamps,  and  starting  switch.  D 
is  cable  containing  wires  leading  from  the  terminal  block  to 

42 


DESCRIPTION"  OF  PARTS 


the  Ford,  ammeter  and  the  combination  lighting  and  ignition 
switch  on  the  instrument  panel  in  front  of  the  driver.  E  is 
cable  containing  wires  leading  from  low  tension,  or  primary 
ignition  coil  terminals,  marked  P,  to  the  commutator.  One 
end  of  each  high  tension  winding  is  also  connected  to  P.  It 
also  contains  two  wires  leading  from  terminal  block  as  shown, 
to  the  right  headlamps.  F  is  common  terminal  which  is 
connected  to  one  end  of  the  low  tension  or  primary  winding 
of  each  Ford  ignition  coil.  H  is  wire  leading  from  cutuot 
to  Ford  ammeter  on  the  instrument  panel  in  front  of  the 
driver.  S  are  terminals  connected  to  one  end  of  the  high 
tension,  or  secondary  winding  of  each  Ford  Ignition  Coil. 

through  the  motor  armature  by  means  of  the  two  un- 
grounded brushes,  to  the  frame  of  the  motor  through  the 
two  grounded  brushes,  through  the  motor  frame  into  the 
car  frame,  through  the  car  frame  back  to  the  cable  from 
the  negative  ( — )  battery  terminal  which  is  attached  to 
the  frame,  through  this  cable  to  the  negative  ( — )  ter- 
minal on  the  battery. 

2.  IGNITION  CIRCUITS,  a.  When  Using  the  Bat- 
tery. From  the  positive  terminal  on  the  battery  to 
the  starting  switch,  along  the  yellow  wire  attached  to  the 
starting  switch  to  the  second  terminal  from  the  left  on 
the  terminal  board,  along  the  second  yellow  wire  attached 
to  this  terminal  down  into  the  cable  that  goes  through 
the  hole  in  the  dash  just  below  the  terminal  board,  up 
to  the  ammeter,  through  the  ammeter  to  the  "Bat"  ter- 
minal on  the  back  of  the  lighting  switch,  through  the 
switch  to  the  "Coil"  terminal  on  the  back  of  the  switch, 
through  the  black  wire  attached  to  this  switch  terminal 
to  the  terminal  in  the  lower  right  hand  corner  of  the  set 
of  ignition  coil  terminals  on  the  dash,  through  the  low 
tension  windings  and  the  vibrators  on  the  ignition  coils, 
out  by  the  upper  row  of  ignition  coil  terminals,  through 
the  wires  that  go  into  the  cable  that  leads  to  the  ignition 
commutator,  and  to  ground.  If  the  ignition  key  is  turned 
to  the  "Bat"  position  when  the  engine  is  running  at  15- 

43 


DESCRIPTION  OF  PARTS 

20  miles  per  hour,  the  generator  will  furnish  the  ignition 
current.  In  this  case  the  circuit  is  the  same  as  that  of 
the  charging  current  as  far  as  the  ammeter.  From  the 
ammeter  the  circuit  is  the  same  as  for  the  battery  igni- 
tion current. 

This  completes  the  low  tension  part  of  the  ignition  cir- 
cuit. The  high  tension  part  starts  in  the  high  tension 
windings  of  the  ignition  coils,  goes  out  at  the  lower  row 
of  coil  terminals,  along  the  cables  to  the  spark  plugs, 
across  the  gaps,  to  the  engine,  then  back  to  the  coil 
through  the  commutator  and  along  wires  that  lead  from 
one  end  of  the  low  tension  winding  of  the  coil  to  the 
commutator.  One  end  of  the  high  tension  winding  is 
therefore  connected  to  one  end  of  the  low  tension  wind- 
ing. The  internal  coil  connections  are  shown  in  Fig- 
ure 42,  page  115. 

b.  When  using  the  Ford  Magneto.  From  the  ter- 
minal on  top  of  the  magneto,  through  the  red  wire  at- 
tached to  this  terminal,  into  the  cable  at  the  right  hand 
side  of  the  dash,  as  you  look  at  the  dash  from  front  end 
of  car,  to  the  left  hand  terminal  on  the  terminal  board, 
along  the  second  red  wire  attached  to  this  terminal, 
through  the  cable  which  passes  through  the  dash  just  be- 
low the  terminal  board,  to  the  terminal  on  the  back  of 
the  lighting  and  ignition  switch  which  is  marked  "Mag", 
through  the  switch  to  the  terminal  on  the  back  of  the 
switch  which  is  marked  "Coil,"  and  then  through  the 
same  wires  and  paths  already  described  for  the  battery  ig- 
nition current. 

3.  CHARGING  CIRCUIT.  (For  cars  with  cutout  on 
dash.  For  circuits  of  new  cutout,  see  page  55.)  From  the 
armature  of  the  generator  through  the  cutout,  through 
the  insulated  upper  frame  work  of  the  cutout,  through  the 
cutout  contact  points,  through  the  heavy  wire  winding  on 
the  cutout  to  the  "Bat"  terminal  on  the  cutout,  through 
the  black  wire  attached  to  the  cutout  to  the  ammeter, 

44 


DESCRIPTION  OF  PARTS 

through  the  ammeter  and  the  yellow  wire  which  is 
attached  to  the  ammeter,  and  which  leads  into  the 
cable  containing  the  wires  attached  to  the  back  of  the 
lighting  and  ignition  switch,  to  the  second  terminal 
from  the  left  on  the  terminal  board  into  the  cable  at  the 
right  side  of  the  dash,  as  you  look  at  dash  from  front  of 
car,  along  the  yellow  wire  coming  from  the  lower  end  of 
this  cable  to  the  starting  switch,  along  the  heavy  starting 
cable  to  the  positive  (+)  battery  terminal,  through  the 
battery  and  out  at  the  negative  ( — )  terminal,  through 
the  cable  fastened  to  the  negative  ( — )  battery  terminal, 
into  and  through  the  car  frame,  through  the  frame  of  the 
generator,  into  the  generator  brush  ring,  through  the 
grounded  main  generator  brush,  and  back  into  the  arma- 
ture. 

4.  LIGHTING  CURRENT.  From  the  battery  to  the 
"Bat"  terminal  on  the  back  of  the  lighting  and  ignition 
switch,  through  the  same  wires  as  for  the  battery  igni- 
tion current.  From  the  switch  the  circuits  are  as  follows: 

(a)  Large   Bulbs  in  Headlights.     From  the   "Head" 
terminal    on    the    back    of    the    lighting    switch    along 
the  gray  wire  attached  to  this  terminal,  down  into  the 
cable  which  connects  the  switch  and  ammeter  to  the  ter- 
minal board,  to  the  right  hand  terminal  on  the  terminal 
board.     From  this  terminal  one  gray  wire  goes  into  the 
cable   at  the  right  hand  side   of  the  dash    (facing  the 
dash),  then  to  the  large  bulb  in  the  left  hand  headlight, 
through  the  bulb  into  the  frame  of  the  car,  through  the 
frame  of  the  car  back  to  the  negative  battery  terminal. 
A  second  gray  wire  leads  from  the  right  hand  terminal 
on  the  terminal  board  into  the  cable  at  the  opposite  side 
of  the  dash  and  to  the  large  bulb  in  the  right  hand  head- 
light, through  the  bulb,  through  the  frame  of  the  car, 
and  back  to  the  negative  battery  terminal. 

(b)  Small  Bulbs  in  the  Headlights.    From  the  "Aux" 
or  "Dim"  terminal  on  the  back  of  the  lighting  switch, 
along   the  brown   wire   attached   to   this   terminal   into 

45 


STARTING  AND  LIGHTING  TROUBLES 

the  cable  that  connects  the  terminal  board  to  the  light- 
ing switch  and  ammeter,  to  the  second  terminal  from 
the  right  on  the  terminal  board  (facing  the  terminal 
board) .  From  here  two  brown  wires  lead.  One  goes  into 
the  cable  at  the  right  hand  side  of  the  dash  (facing  the 
dash),  thence  directly  to  the  small  bulb  in  the  left  head- 
light, through  the  small  bulb,  through  the  frame  of  the 
car  and  back  to  the  negative  battery  terminal.  The  sec- 
ond brown  wire  leads  from  the  terminal  board  into  the 
cable  at  the  left  hand  side  of  the  dash  (facing  the  dash), 
thence  directly  to  the  small  bulb  in  the  right  hand  head 
lamp,  through  the  bulb,  through  the  frame  of  the  car 
back  to  the  negative  terminal  of  the  battery. 

(c)  Tail  Lamp.  From  the  terminal  on  the  back  of 
the  lighting  switch  which  is  marked  "Tail,"  along  the 
green  wire  which  is  attached  to  this  terminal,  into  the 
cable  which  connects  the  terminal  board  to  the  ammeter 
and  lighting  switch,  through  this  cable  to  the  third  ter- 
minal from  the  left  on  the  terminal  board,  along  the  sec- 
ond green  wire  which  is  attached  to  this  terminal  down 
into  the  cable  at  the  right  hand  side  of  the  dash  (facing 
the  dash),  out  of  this  cable  at  the  lower  end  and  along 
the  green  wire  directly  to  the  tail  lamp  bulb,  through  the 
bulb  to  the  frame  of  the  car,  through  the  frame  of  the 
car  back  to  the  negative  battery  terminal. 

5.  GENERATOR  FIELD  CURRENT.  From  the  third 
brush  to  the  upper  left  hand  field  coil  (facing  the  ter- 
minal end  of  the  generator)  through  this  field  coil  to  the 
upper  right  hand  coil,  through  the  upper  right  hand  coil 
to  the  lower  right  hand  coil,  through  the  lower  right 
hand  coil  to  the  lower  left  hand  coil,  through  the  lower 
left  hand  coil  to  the  grounded  main  brush,  through  the 
armature  windings  back  to  the  third  brush. 

TROUBLES  IN  THE  STARTING  AND  LIGHTING 

SYSTEM. 
Troubles  that  occur  in  the  electric  starting  and  light- 

46 


STARTING  AND  LIGHTING  TROUBLES 

ing  system  may  be  classified  as  follows: 

1.  Troubles  that  occur  when  the  engine  is  not  run- 
ning and  all  lamps  are  off. 

2.  Troubles  that  occur  when  the  engine  is  not  run- 
ning and  the  lamps  are  turned  on, 

3.  Troubles  that  occur  when  the  engine  is  running 
and  the  lamps  are  turned  off. 

4.  Trouble  with  the  starting  motor,  or  in  the  starting 
motor  circuit. 

These  four  classes  will  include  any  troubles  that  may 
arise  in  the  starting  and  lighting  system.  These  troubles 
may  be  best  handled  by  a  set  of  instructions  which  we 
may  call  Charts.  In  the  Ambu  Electric  Trouble  Shooter, 
there  are  twelve  such  charts  and  the  same  system  will  be 
followed  here.  Considering  the  four  classifications  just 
given,  we  have: 

1.  ENGINE   NOT   RUNNING,    LAMPS   OFF.     Under 
these  conditions,  every  electrical  part  and  unit  on  the  car 
should  be  at  rest  and  there  should  be  no  flow  of  current 
anywhere.     Since  the  generator  is  now  at  rest,  it  cannot 
deliver  any  current.     The  battery,  however,  is  capable  of 
delivering  a  current,  and  therefore  the  only  trouble  that 
can  occur  under  these  conditions  consists  of  a  flow  of  cur- 
rent from  the  battery,  the  causes  of  which  are  taken  up 
in  Chart  No.  1,  page  53. 

2.  ENGINE  NOT  RUNNING,  LAMPS  ON.     Troubles 
that  can  occur  under  these  conditions  are  all  concerned 
with  the  lighting  system.    The  lights  may  or  may  not  be 
drawing  the  proper  current  from  the  battery.    If  all  the 
lights  burn  satisfactorily,  and  draw  the  proper  current 
from  the  battery,  no  trouble  is  present.     If  the  lamps  do 
not  draw  the  right  amount  of  current,  they  may  be  draw- 
ing none  at  all,  too  much  current,  or  not  enough  current. 
These  conditions  are  taken  care  of  in  charts  3,  4  and  5  on 
pages  65,  69  and  71,  respectively. 

47 


STARTING  AND  LIGHTING  TROUBLES 

3.  ENGINE  RUNNING,   LAMPS  OFF.  Troubles  that 
occur  under  these  conditions  affect  the  charging  circuit, 
consisting  of  the  generator,  cutout,  ammeter,  battery,  and 
the  wires  that  carry  the  charging  current  from  the  gen- 
erator to  the  battery. 

We  may  have  the  correct  charging  current,  which,  of 
course,  is  not  a  condition  of  trouble.  We  may  have  no 
charging  current,  not  enough  charging  current,  too  much 
charging  current,  or  else  the  current  in  the  charging  cir- 
cuit may  be  reversed.  These  troubles  are  taken  care  of  in 
Charts  7,  8,  9  and  10,  on  pages  77,  84,  87  and  103,  re- 
spectively. 

4.  STARTING  TROUBLE.     The  duty  of  the  starting 
motor  is  to  crank  the  engine.    If  it  fails  to  do  this,  there 
is  trouble  in  the  motor  itself,  in  the  circuit  between  the 
motor  and  the  battery,  or  in  the  battery.    These  troubles 
are  taken  care  of  in  Chart  12,  page  107. 

TESTING  FOR  TROUBLE.  All  troubles  in  the  starting 
and  lighting  system  affect  the  flow  of  current  in  or  out 
of  the  battery,  especially  in  the  first  three  of  the  four 
classes  just  described.  Therefore,  the  best  way  to  make 
tests  in  locating  troubles  is  to  connect  an  ammeter  in 
series  with  the  battery.  This  is  the  method  used  in  the 
Ambu  Electric  Trouble  Shooter.  The  Ambu  instrument 
is  a  combined  ammeter  and  voltmeter.  Directions  for 
using  it  are  given  in  a  special  Ambu  Instruction  Book. 
The  instrument  is  connected  in  series  with  the  battery, 
using  the  25  ampere  scale.  This  is  done  by  removing  the 
cable  from  the  positive  terminal  post  on  the  battery,  and 
then  connecting  the  cable  to  one  terminal  of  the  instru- 
ment, and  connecting  the  positive  post  of  the  battery  to 
the  other  terminal  on  the  instrument,  as  shown  in  Figure 
22.  With  the  instrument  connected  in  this  manner,  all 
current  passing  in  or  out  of  the  battery  must  now  pass 
through  your  ammeter.  This  ammeter  will  hereafter  be 
referred  to  as  "your  ammeter,"  to  distinguish  it  from  the 

48 


STARTING  AND  LIGHTING  TESTS 


ammeter  mounted  on  the  dash  of  the  car,  which  will  be 
referred  to  as  the  "Ford  ammeter." 

With  your  ammeter  connected  in  series  with  the  bat- 
tery, make  three  tests  under  the  following  conditions: 

1.  ENGINE  NOT  RUNNING,  LAMPS  OFF. 

2.  ENGINE  NOT  RUNNING,  LAMPS  ON. 

3.  ENGINE  RUNNING,  LAMPS  OFF. 
Let  us  now  make  these  tests: 

1.  ENGINE  NOT  RUNNING,  LAMPS  OFF.  Make 
sure  that  the  ignition  and  all  the  lamps  are  switched  off. 
Now  look  at  the  pointer  on  your  ammeter.  If  the  pointer 


25         + 

EXTRA    V 
THIS   COh 

VIRE   TO&OAKE 
JNE.CTION 

.   GL^ 

^o 

HD 
0— 

OABL.E    REMOVED  FROM  THE 
•*•  TERMINAL.    POST  ON  THE 
BATTER-  V 

o= 

HOW  TO  CONNECT    METER   IN  SERIES   WITH 
BATTERV     IN  ORDER  TO    IV1AKE   TESTS    ON   START- 
ING  8*    LIGHTING     SYSTEM 

FIGURE  22. 

moves  backward,  see  Chart  2,  page  64.  If  it  moves  from 
the  "0"  line  on  the  scale,  indicating  that  current  is  flow- 
ing through  your  ammeter,  turn  to  Chart  1,  page  53. 
Here  you  will  find  a  diagram  of  that  part  of  the  electrical 
system  in  which  the  trouble  causing  the  flow  of  current 
may  exist.  Below  the  diagram  begins  a  set  of  instruc- 
tions for  finding  the  trouble.  If  the  pointer  does  NOT 
move,  no  trouble  is  present,  and  you  should  proceed  to 
make  the  next  test. 

2.  ENGINE  NOT  RUNNING,  LAMPS  ON.  Turn  the 
handle  on  the  lighting  switch  to  the  "ON"  position. 
Then  look  at  the  pointer  on  your  meter.  It  should  be 
over  the  "5.4"  ampere  line  on  the  scale.  Should  the 

40 


STARTING  AND  LIGHTING  TESTS 

pointer  not  move,  the  entire  lighting  system  is  dead, 
and  no  lights  burn.  If  this  is  the  case,  see  Chart  3,  which 
begins  on  page  65.  Should  the  pointer  indicate  much  less 
than  5.4  amperes,  see  Chart  5,  which  begins  on  page  71. 
Should  the  pointer  indicate  more  than  5.4  amperes,  see 
Chart  4,  beginning  on  page  69.  Now  turn  the  handle  of 
the  lighting  switch  to  the  "Dim"  position.  This  will 
cause  the  tail  light,  and  the  small  bulbs  in  the  head  lamps 
to  burn.  The  ammeter  pointer  should  move  to  the  1.25 
ampere  line  on  the  scale.  If  it  indicates  less  current  than 
this,  see  Chart  5,  beginning  on  page  71.  If  it  indicates 
more  current  than  this,  see  Chart  4,  beginning  on  page 
69.  Having  consulted  one  of  these  charts,  according  to 
the  above  instructions,  in  case  the  pointer  did  not  indicate 
1.25  or  5.4  amperes,  and  having  followed  the  instructions 
in  the  Chart  which  you  consulted,  you  will  have  found 
any  trouble  which  may  have  existed  in  the  lighting  cir- 
cuits and  are  now  ready  to  make  the  third  test. 

3.  ENGINE  RUNNING,  LAMPS  OFF.  Turn  the  han- 
dle of  the  lighting  switch  to  the  "Off"  position.  Short 
circuit  your  ammeter,  or  remove  it  temporarily,  and  re- 
place the  battery  cable  in  the  positive  (+)  battery  ter- 
minal post.  The  purpose  of  this  is  to  prevent  the  heavy 
current  drawn  from  the  battery  by  the  starting  motor 
from  damaging  your  ammeter.  Turn  the  ignition  key  to 
the  "Bat"  position,  and  start  the  engine  with  the  starting 
motor.  As  soon  as  the  engine  is  running  under  its  own 
power,  turn  the  ignition  key  to  the  "Mag"  position. 
Then  connect  your  ammeter  in  series  with  the  battery  as 
before,  but  reverse  the  connections  to  the  meter,  as  cur- 
rent is  now  being  delivered  to  the  battery  instead  of  be- 
ing drawn  from  it.  The  cable  removed  from  the  battery 
should  now  be  connected  to  the  "-(-"  terminal  on  your 
ammeter,  and  the  positive  battery  post  to  the  " — "  or 
"25"  terminal  on  your  ammeter  (see  Figure  23).  Be 
careful  to  connect  in  your  ammeter  as  quickly  as  pos- 
sible, as  the  generator  must  not  be  run  except  for  a 

50 


STARTING  AND  LIGHTING  TESTS 


very  short  time  only  with  the  charging  circuit  open. 
With  the  engine  running  at  a  speed  which  would 
drive  the  car  on  the  road  at  20  miles  per  hour  in 
high  gear,  look  at  the  pointer  of  your  ammeter.  It 
should  be  over  the  10  ampere  line  on  the  scale,  and 
should  move  in  the  same  direction  from  the  "0"  line  as 
it  did  when  the  test  was  made  with  the  Engine  Not  Run- 
ning, and  the  Lamps  On.  If  the  pointer  moves  in  the  op- 
posite direction  to  this,  the  current  in  the  charging  cir- 
cuit is  flowing  in  the  wrong  direction  and  Chart  8,  begin- 


EXTRA  WIRE 


CABLE   REMOVED    FROM    + 
POST  ON  BATTERV 


BATTEPY 


CONNECTIONS  OF  METER  IN  MAKINQ   TEST    "ENGINE 
RUNNING,   LAMPS   OFF* 

FIGURE  23. 


ning  on  page  84,  should  be  consulted.  If  the  pointer 
moves  in  the  right  direction,  but  does  not  move  as  far  as 
the  10  ampere  line,  consult  Chart  9,  beginning  on  page 
87.  If  the  pointer  moves  in  the  right  direction,  but 
moves  farther  than  the  10  ampere  line,  consult  Chart  10, 
beginning  on  page  103.  If  the  pointer  does  not  move  at 
all,  consult  Chart  7,  beginning  on  page  77. 

IF  THE  POINTER  FLUCTUATES.  If,  in  making  any 
test,  the  pointer  does  not  come  to  rest,  but  moves  about 
in  an  irregular,  jerky  manner,  consult  Chart  11,  begin- 

ol 


STAKTING  AND  LIGHTING  TESTS 


ning  on  page  105. 

STARTING  TROUBLE.  If  the  starting  motor  fails  to 
crank  the  engine  satisfactorily,  consult  Chart  12,  begin- 
ning on  page  107.  It  is  not  necessary  to  measure  the 
starting  current,  as  the  current  may  vary  from  140  to 
300  amperes  and  still  there  may  be  no  trouble  in  the 
starting  motor  or  its  circuit. 

SPECIAL  NOTES  ON  TROUBLES. 

SYMPTOMS.  Generator  stops  charging  suddenly  as 
engine  is  speeded  up.  This  has  been  found  to  be  due  in 
most  instances  to  spring  on  third  brush  being  weak,  or 
high  mica  on  commutator.  The  third  brush  breaks  con- 
tact with  commutator  at  the  high  speeds. 

Consult  page  32,  for  troubles  caused  by  short  circuits 
on  the  back  of  the  old  style  lighting  switch. 

SPECIAL  INSTRUCTIONS. 

1.  IF  LAMPS  BURN  OUT  WHEN   THEY   ARE  TURNED 
ON    WHILE    ENGINE    IS    RUNNING    AT    SPEED    CORRE- 
SPONDING   TO    20    MILES    PER   HOUR    IN    HIGH    SPEED, 
there  is  a  loose  connection  between  the  battery  and  lighting 
switch,  or  else  the  generator  is  charging  at  too  high  a  rate. 
Connect  ammeter  in  series  with  battery,  turn  off  the  lamps, 
and  read  charging  current.     If  this  amounts  to  less  than  10, 
or  if  there  is  no  charging  current,  see  Chart  7,  page  77.     If  it 
is  more  than  10  amperes,  see  Chart  10,  Page  103. 

Also  examine  the  battery  by  removing  the  vent  cap  from 
each  cell.  Look  down  into  each  cell,  and  if  the  level  of  the 
electrolyte  has  fallen  below  the  tops  of  the  plates,  pour  in 
distilled  water  until  it  covers  plates  about  %  of  an  inch. 

2.  IF    LAMPS    BURN    DIMLY    WHEN    ENGINE    IS    NOT 
RUNNING,  AND  BURN  OUT  IF  TURNED  ON  WHILE  EN- 
GINE IS  RUNNING,  follow  the  same  instructions  given  above 
in  Section  1. 


CHART  1 


ENGINE  NOT  RUNNING  FORD— CHART  1 

LAMPS  OFF  F.  A,  SYSTEM 

TO  BE  CONSULTED  IF  THERE  IS  A  DIS- 
CHARGE OF  CURRENT  FROM  THE  BATTERY, 
WHICH  SHOULD  NOT  TAKE  PLACE  WITH 
THE  ENGINE  NOT  RUNNING,  AND  THE 
LIGHTING  AND  IGNITION  SWITCHES 
TURNED  OFF. 


FORD  'FA*  SYSTEM 
CHART   1 

FIGURE  24. 
FOR  CARS  HAVING  CUTOUT  ON  DASH. 

NOTE.  First  inspect  all  the  wiring  for  damaged  in- 
sulation which  allows  the  wires  to  make  contact  with 
the  metal  of  the  car.  If  none  is  found,  proceed  with  the 
following  instructions. 

53 


CHART  1 


FIGURE  24a. 
FOR  CARS  HAVING  CUTOUT  ON  GENERATOR. 

A.     CLOSED  CUTOUT  OR  OTHER  CUTOUT  TROUBLE. 

The  cutout  is  either  mounted  on  top  of  the  generator,  or 
else  is  mounted  on  the  dashboard  just  inside  the  engine 
hood  to  the  right  of  the  engine. 

TESTS  FOR  CUTOUT  WHICH  IS  MOUNTED  ON  THE 

DASH, 

TEST.  Remove  the  wire  from  the  "Bat"  terminal  of 
the  cutout.  Then  look  at  your  ammeter.  If  ammeter 
pointer  now  goes  back  to  the  "0"  line,  read  the  instructions 
given  in  the  next  "Remedy"  paragraph.  If  the  pointer 
does  not  return  to  the  "0"  line,  consult  Section  B. 

54 


.  CHAET  1 

CUTOUT 


CONTACT     POINTS 
INSULATED    PLATE 


QROU/ND 


QENERATOR    FRAME 

FIGURE  24b. 

INTERNAL    CONNECTIONS    OF    CUTOUT    MOUNTED    ON 
GENERATOR 

REMEDY.  There  is  trouble  in  the  cutout.  Replace 
the  wire  which  you  removed  from  the  "Bat"  terminal 
on  the  cutout.  If  the  pointer  does  not  now  move  away 
from  the  "0"  line,  the  trouble  was  caused  by  the  cutout 
contact  points  having  been  closed,  but  opening  when 
the  wire  was  removed  from  the  "Bat"  terminal.  The  con- 
tact points  should  be  made  smooth  with  fine  emery  cloth 
or  a  fine  tooth  file  so  that  they  will  not  stick  together 
when  the  engine  is  stopped  the  next  timev 

If  the  pointer  again  moved  away  from  the  "0"  line 
when  you  replaced  the  wire  on  the  "Bat"  terminal  on 
the  cutout,  pry  oif  the  cover  with  the  tip  of  a  screw- 
driver. Examine  the  contact  points  which  are  under 
the  movable  arm  at  one  end.  You  will  probably  find 
that  they  are  stuck  together.  If  this  is  the  case  sepa- 
rate them  and  make  them  perfectly  smooth  with  fine 
emery  cloth  or  a  fine  toothed  file  so  they  will  not  stick 
together  the  next  time  the  engine  is  stopped.  Make  sure 
of  this  by  starting  the  engine,  running  it  fast  enough  to 

55 


CHART  1 

close  the  cutout  and  then  stopping  it  and  examining-  the 
points  to  see  whether  they  still  stick  together. 

If  you  found  that  the  cutout  contact  points  were  not 
stuck  together,  there  must  be  trouble  in  the  cutout  wind- 
ings. These  may  be  tested  for  as  described  below,  using 
a  circuit  tester  made  of  a  lamp  as  shown  on  page  57, 
Figures  25  or  26. 

(a)  CURRENT  COIL  TROUBLE— TEST.  Remove  the 
wires  which  are  connected  to  the  "Gen"  and  "Bat"  ter- 
minals. Now  hold  one  test  point  on  the  "Bat"  terminal, 
and  hold  the  other  test  point  on  the  middle  terminal  on 
the  cutout.  If  the  lamp  lights  consult  the  next  paragraph 
starting  "Remedy".  If  the  lamp  does  not  light  consult 
Section  B. 

REMEDY.  There  is  a  ground  in  the  current  coil,  or 
the  current  coil  is  short  circuited  with  the  voltage  coil, 
or  else  the  stationary  cutout  contact  point  is  making  a 
metallic  connection  with  the  part  on  which  it  is  mounted. 

Remove  the  screw  which  holds  the  stationary  contact 
point  in  place.  Hold  this  contact  point  clear  of  any 
other  metal  part  of  the  cutout,  and  repeat  the  test  by 
holding  one  test  point  on  the  "Bat"  terminal,  and  the 
other  on  the  middle  terminal  on  the  cutout.  If  the  lamp 
lights,  the  trouble  is  still  present.  If  the  lamp  now  does 
not  light,  the  stationary  contact  point  was  grounded  to 
the  part  on  which  it  was  mounted,  and  new  insulation 
should  be  put  under  it. 

If  the  lamp  lighted,  disconnect  the  heavy  wire  from 
the  under  side  of  the  "Bat"  terminal  on  the  cutout.  Now 
hold  one  test  point  on  the  wire  which  you  removed  from 
the  "Bat"  terminal,  and  hold  the  other  test  point  on  the 
middle  terminal  on  the  cutout.  If  the  lamp  lights  the 
current  coil  is  grounded,  or  else  short  circuited  to  the 
voltage  coil.  If  the  lamp  lighted,  it  will  be  necessary 
to  unwind  the  coils  of  the  cutout  until  the  short-circuit 
or  ground  is  found,  and  the  wires  reinsulated  at  this  point 
and  rewound.  If  new  cutouts  are  available,  it  will  be 

56 


CHART  1 

best  to  put  in  a  new  one.  If  the  lamp  does  not  light,  the 
"Bat"  terminal  is  grounded  to  the  base  of  the  cutout,  and 
new  insulation  should  be  put  under  it. 

TESTS  FOR  CUTOUT  MOUNTED  ON  GENERATOR- 
TEST.  Remove  the  wire  from  the  cutout  terminal. 
Then  look  at  your  ammeter.  If  the  pointer  has  now  gone 
back  to  the  "0"  line  on  the  scale,  read  the  instructions 
starting  with  the  following  "Remedy"  paragraph.  If 
the  pointer  has  not  returned  to  the  "0"  line,  consult  Sec- 
tion B. 

REMEDY.     There  is  trouble  in  the  cutout.     Replace 

NEITHER    BATTERY   TERM- 
INAL    SHOULD   BE    ^ROUNDED 


v 


AO  OR  60 

WATT  UAMP 

no  VOL.TS 


6  VOLT  BATr- 

RV    OR    •**• 
DRV   CELLS 


0 


POINTED    BRASS  RODS 
USED  AS  TEST    POINTS 


POINTED   BRASS    RODS 
USE  DAS  TEST  POINTS 


TWO    WAYS  OF  MAKING  A  CIRCUIT   TESTER,    USIN.Q  A  LAMP 

FIGURE    25.  FIGURE    26. 

the  wire  on  the  cutout  terminal.  If  pointer  now  does 
not  move  away  from  the  "0"  line  on  your  ammeter,  con- 
sult paragraph  (a)  below.  If  pointer  again  moves  away 
from  the  "0"  line  when  you  replace  the  wire  on  the 
cutout,  consult  paragraph  (b)  below. 

(a)  CUTOUT  FAILED  TO  OPEN  THE  LAST  TIME 
ENGINE  WAS  STOPPED.  If  pointer  does  not  move 
away  from  the  "0"  line  as  you  replace  this  wire,  the 


57 


CHART  1 

cutout  contact  points  were  closed  but  they  separated 
when  you  removed  the  wire  from  the  cutout.  The  cause 
of  the  points  being  closed  may  have  been  as  follows: 

If,  when  the  engine  is  running,  and  the  generator  is 
charging  the  battery,  the  generator  circuit  between  the 
generator  and  the  cutout  is  suddenly  opened  by  the  break- 
ing of  a  wire,  by  a  brush  being  suddenly  stuck  in  its 
holder  so  as  to  prevent  it  from  touching  the  commutator, 
etc.,  the  cutout  will  probably  remain  closed.  The  bat- 
tery will  send  enough  current  through  the  voltage  coil 
of  the  cutout  when  the  generator  circuit  is  suddenly 
opened  to  keep  the  cutout  closed.  The  sudden  opening 
of  the  generator  circuit  prevents  the  battery  from  be- 
ginning to  discharge  back  into  the  generator,  which 
would  reverse  the  current  through  the  current  coil  of 
the  cutout.  This  reverse  current  is  necessary  to  demag- 
netize the  cutout,  and  cause  the  spring  to  pull  the  con- 
tacts apart.  "When  you  removed  the  wire  from  the  cut- 
out, the  battery  was  disconnected  from  the  voltage  coil 
and  the  spring  therefore  opened  the  cutout.  Replacing  the 
battery  wire  on  the  cutout  will  not  cause  it  to  close  again 
because  the  points  must  be  closed  before  the  battery  can 
send  current  into  the  voltage  coil. 

(b)  CUTOUT  CONTACT  POINTS  STUCK  TOGETHER, 
OR   OTHER   CUTOUT   TROUBLE.     If   pointer   on  your 
ammeter  again  moved  away  from  the  "0"  line  when  you 
replaced  the  wire  on  the  cutout,  take  out  the  screw  in 
the  cover  which  is  marked  "A"  in  Figure  24B.    Then 
pry  off  the  cutout  cover.     If  your  ammeter  pointer  goes 
back  to  "0"  when  you  remove  the  cover  and  hold  the 
cover  away  from  any  metallic  part  of  the  car  one  of 
the  following  troubles  may  be  present: 

(c)  CONTACT  POINTS  STUCK  TOGETHER.     If  you 
find  the  contact  points  to  be  stuck  together,  force  them 
apart  and  make   them  perfectly  smooth  by  drawing  a 
piece  of  fine  emery  cloth  or  a  fine  toothed  file  between 

58 


CHART  1 


them,  so  that  they  will  not  stick  together  again  the  next 
time  the  engine  is  stopped.  Make  sure  of  this  by  replac- 
ing the  cutout  cover,  running  the  engine  (see  precau- 
tions, page  50,  about  short  circuiting  your  ammeter)  fast 
enough  to  close  the  contact  points,  and  then  stopping  the 
engine.  If  your  ammeter  pointer  now  does  not  move 
away  from  the  "0"  line,  the  contact  points  did  not  stick 
together. 

(d)  COVER  SCREWS  A  OR  B   (SEE  FIGURE  24B) 
GROUNDED    TO    CUTOUT    COVER— TEST.     With    the 
wire  still  attached  to  screw  B  on  the  cutout  cover,  touch 
the  cutout  cover  to  the  oiler  at  the  rear  end  of  the  gen- 
erator so  as  to  ground  it.    If  the  pointer  on  your  ammeter 
now  moves  away  from  the  "0"  line  again,  screw  B  is 
grounded  to  the  cutout  cover.     If  the  pointer  does  not 
move  from  the  "0"  line,  push  screw  "A"  through  its  hole 
in  the  cover  and  hold  it  in  place  firmly.     Now  touch  the 
cutout  cover  to  the  oiler  at  the  rear  end  of  the  generator 
again.     If  pointer  on  your  ammeter  now  moves  away 
from  the  "0"  line,  screw  "A"  is  grounded  to  the  cover. 
If  pointer  does  not  move  in  either  test,  see  (e)  below. 

REMEDY.  Renew  the  insulation  under  screws  A  and 
B,  or  see  if  holes  in  cover  are  so  small  that  screws  touch 
cover  when  they  are  screwed  in. 

(e)  PIECE   C    (SEE   FIGURE   24B)    OR   CURRENT 
COIL    ON    CUTOUT    GROUNDED— TEST.     Use    a    lamp 
circuit  tester  as  shown  in  Figure  25  or  26,  page  57.    Hold 
one  test  point  on  piece  C  and  hold  other  test  point  on 
the  base  of  the  cutout.    If  lamp  lights,  piece  C  or  current 
coil  are  grounded  to  the  base,  or  current  coil  is  short  cir- 
cuited with  voltage  coil,  and  following  "Remedy"  should 
be  consulted. 

REMEDY.  Carefully  inspect  the  ends  of  the  wire  of 
the  current  coil.  See  that  they  do  not  touch  anything 
but  pieces  C  and  D  (see  Figure  24B)  to  which  they  are 
soldered,  If  these  wires  are  clear  from  all  other  parts, 

59 


CHART  1 

unsolder  them  from  pieces  C  and  D.  Test  pieces  C  and 
D  for  ground  by  holding  one  test  point  on  base  of  cutout 
and  holding  other  test  point  on  each  piece,  C  and  D 
separately.  If  lamp  lights  as  either  C  or  D  are  tested, 
that  piece  is  grounded  to  the  base,  and  the  insulation  is 
defective  and  must  be  replaced. 

If  pieces  C  and  D  are  not  grounded,  the  current  coil 
is  grounded  to  part  M  or  is  short  circuited  with  the  volt- 
age coil.  In  either  case,  it  is  best  to  install  a  new  cut- 
out. If  you  want  to  repair  the  cutout,  take  it  apart  by 
removing  the  screw  which  turns  up  into  the  cutout  from 
beneath.  Unwind  the  coils  until  the  defective  insulation 
is  found.  Reinsulate,  and  rewind  coils. 

OTHER  CUTOUT  TROUBLE. 

(f)  If  the  insulation  on  the  current  coil  is  all  burned 
off  and  the  coil  is  short  circuited  between  turns,  this  may 
prevent   cutout   from   opening  when   engine   is   stopped, 
although  it  would  not  prevent  cutout  from  closing  prop- 
erly.    If  this  is  the  case,  put  in  a  new  cutout  or  else 
remove  the  current  coil  and  reinsulate  it. 

(g)  Make  sure  that  the  spring  which  is  supposed  to 
hold  the  contact  points  open  is  not  weak,  bent,  or  broken, 
or  has  not  slipped  out  from  under  the  hook  at  its  free  end, 
and  that  the  spring  with  which  the  arm  is  mounted  is  not 
bent  so  as  to  force  the  contact  points  together. 

B.  STARTING  SWITCH  SHORT  CIRCUITED  OR 
GROUNDED.  The  starting  switch  is  located  under  the 
floorboards  in  front  of  the  driver.  It  may  be  inspected 
from  underneath  the  car.  The  terminal  on  the  switch  which 
is  toward  the  rear,  and  which  is  connected  to  the  battery, 
also  has  a  smaller  yellow  wire  connected  to  it.  Remove 
this  yellow  wire,  and  the  large  cable  from  this  terminal, 
and  hold  their  ends  together.  Now  look  at  the  pointer 
on  your  ammeter.  If  it  has  gone  back  to  the  "0"  line, 
consult  the  next  paragraph.  If  it  still  indicates  that 
current  is  flowing  from  the  battery,  replace  the  cable  and 

60 


CHART  1 

yellow  wire  on  the  starting  switch  and  consult  section 
C. 

REMEDY.  The  starting  switch  is  defective.  Discon- 
nect the  cable  leading  to  the  motor.  Remove  switch  by 
taking  out  the  two  screws  or  bolts  by  which  it  is  fastened 
to  the  car  frame.  Remove  the  cover  by  taking  out  the 
two  screws  that  hold  it  in  place.  Carefully  inspect  the 
inside  of  the  switch  and  make  sure  that  the  parts  at- 
tached to  the  plunger  are  not  loose  or  bent  so  that  the 
switch  fails  to  open  the  starting  circuit  entirely.  See 
that  there  are  no  pieces  of  brass  or  copper  short  circuiting 
the  contacts. 

C.  TROUBLE  IN  WIRE  BETWEEN  STARTING 
SWITCH  AND  AMMETER.  The  yellow  wire  that  is  at- 
tached to  the  starting  switch  leads  to  the  terminal  board 
on  the  dash  and  then  to  the  Ford  ammeter,  as  shown  on 
the  diagram  at  the  beginning  of  this  Chart.  Disconnect 
this  yellow  wire  from  the  terminal  on.  the  back  of  the 
Ford  ammeter  and  look  at  your  ammeter.  If  the  pointer 
of  your  ammeter  has  gone  back  to  zero,  consult  Section  D. 
If  the  pointer  indicates  that  current  is  still  flowing 
from  the  battery,  consult  the  following  Remedy: 

REMEDY.  The  yellow  wire  leading  from  the  starting 
switch  to  the  Ford  ammeter  is  grounded,  or  short-circuited 
with  one  of  the  other  wires  in  one  of  the  two  cables 
(shown  at  C  and  D  in  Figure  21)  whose  wires  are  con- 
nected to  the  terminal  block.  To  determine  in  which 
cable  the  trouble  is,  first  examine  the  cables  carefully,  and 
inspect  the  yellow  wire  from  the  starting  switch  to  the 
first  cable  (C  in  Figure  21),  and  from  the  terminal  block 
to  where  it  enters  the  second  cable  (D  in  Figure  21).  If 
no  damaged  insulation  can  be  found  which  will  cause  a 
short  circuit  or  ground,  open  all  the  joints  at  the  ter- 
minal block.  If  the  pointer  of  your  ammeter  moves 
to  the  "0"  line,  when  this  has  been  done,  the  trouble 

61 


CHART  1 


is  in  the  cable  (D  in  Figure  21)  leading  from  the  terminal 
block  to  the  Ford  ammeter  and  lighting  switch.  If  your 
ammeter  indicates  that  current  is  still  flowing  from  the 
battery,  the  trouble  is  in  the  cable  (C  in  Figure  21)  at 
the  right  side  of  the  dash  (facing  the  dash).  In  either 
case  put  in  a  new  cable,  or  else  cut  the  outside  insulation 
of  the  cable  carefully  so  as  to  separate  the  wires.  Then 
look  for  the  damaged  insulation  and  repair  it. 

D.  LIGHTING  SWITCH  CLOSED,  SHORT  CIRCUITED 
OR  GROUNDED — TEST.  All  wires  must  be  connected 
in  place,  but  your  ammeter  must,  of  course,  be  left  con- 
nected in  series  with  the  battery.  Remove  the  wire  from 
the  "Bat"  terminal  on  the  lighting  switch.  Look  at  your 
ammeter.  If  the  pointer  has  gone  back  to  the  "0"  line, 
replace  the  wire  on  the  switch  and  consult  the  following 
''Remedy"  paragraph.  If  the  pointer  still  indicates  that 
current  is  flowing  from  the  battery,  see  Section  E. 

REMEDY.  Remove,  one  by  one,  the  wires  from  the 
various  terminals  on  the  back  of  the  lighting  switch, 
but  do  not  remove  the  wire  from  the  "Bat"  terminal. 
Watch  your  ammeter  as  you  remove  each  wire.  If  the 
pointer  does  not  go  back  to  the  "0"  line  when  you  re- 
move a  certain  wire,  replace  it  before  removing  the  next 
wire.  If  the  pointer  goes  back  to  the  "0"  line  when  you 
remove  a  certain  wire,  there  is  a  short  circuit  between 
the  terminal  to  which  that  wire  is  attached,  and  the 
"Bat"  terminal  on  the  switch. 

Remove  and  open  the  switch  and  examine  the  parts 
for  the  short  circuit.  Troubles  that  have  been  found 
with  the  old  style  switch  are  described  on  page  32.  If, 
when  all  wires  have  been  removed  except  the  one  on 
the  "Bat"  terminal,  your  ammeter  indicates  that  cur- 
rent is  still  flowing  from  the  battery,  the  switch  itself 
is  grounded  and  a  careful  inspection  should  be  made  to 
find  the  trouble. 

62 


CHART  1 

E.  OTHER  TROUBLE.     The  only  other  places  where 
the  trouble  may  be  are  the  Ford  ammeter,  the  wire  con- 
necting the  Ford  ammeter  to  the  lighting  switch,  and 
the  wire  connecting  the  Ford  ammeter  to  the   cutout. 
Inspect   these   wires    carefully   for   damaged    insulation 
which  allows  the  wire  to  touch  some  metallic  part  of  the 
car.     If  the  wires  are  not  damaged,  the  Ford  ammeter 
must  be  defective. 

F.  TROUBLE   IN   ACCESSORY    OR    EXTRA   LAMP 
LINES.     Be  sure  that  no  extra  equipment,  such  as  spot- 
lights, cigar  lighters,  handwarmers  on  the  steering  wheel, 
fuel  vaporizers,  etc.,  have  been  added  to  the  regular  equip- 
ment of  the  car.    If  any  such  apparatus  has  been  added, 
make  sure  that  it  is  turned  oif,  and  that  its  wires  do  not 
have  damaged  insulation  at  any  point. 


CHART  2 

CHART  2— FORD  ENGINE  NOT  RUNNING 

F.  A.  SYSTEM  LAMPS  OFF 

REVERSED    METER    CONNECTIONS, 
Should  your  ammeter  pointer  go  backwards  when  you 
connect  it  in  series  with  the  battery,  reverse  the  con- 
nections to  the  meter,  and  consult  Chart  1. 


64 


CHART  3 


ENGINE  NOT  RUNNING 
LAMPS  ON 


FORD— CHART  3 
F.  A.  SYSTEM 


TO  BE  USED  IF  AMMETER  POINTER  DOES 
NOT  MOVE  FROM  THE  "0"  LINE  WHEN 
LIGHTS  ARE  TURNED  ON. 


FIGURE  27. 

A.  OPEN  CIRCUIT  IN  BATTERY,  OR  BATTERY 
"DEAD."  Make  sure  that  the  battery  terminals  are  free 
from  dirt,  and  that  the  top  connectors  are  not  loose.  If 
any  corrosion  is  present,  clean  oif  the  top  of  the  battery 
with  a  rag  wet  with  ammonia  or  a  soda  solution.  If 
a  terminal  is  badly  corroded,  open  the  joint  if  possible 

65 


CHART  3 


and  scrape  off  the  corrosion  before  replacing  the  cable. 
If  it  is  impossible  to  loosen  the  cable,  drill  off  the  ter- 
minal and  boil  it  in  soda  or  ammonia  solution.  If  this 
does  not  help  burn  on  a  new  terminal  and  cable. 

If  the  battery  is  clean  and  very  little  corrosion  is  pres- 
ent, measure  the  voltage  of  each  battery  cell.  If  one  or 
more  cells  show  little  or  no  voltage,  it  is  "dead,"  and 
the  battery  must  be  opened  for  repairs.  Complete  direc- 
tions for  doing  this  are  given  in  the  book  "The  Auto- 
mobile Storage  Battery,  Its  Care  and  Repair,"  published 
by  the  American  Bureau  of  Engineering. 

If  the  voltage  of  each  cell  measured  2  or  more,  see 
Section  B. 

B.  LOOSE  CONNECTIONS  IN  WIRING.     Inspect  all 
the  wiring  as  shown  in  the  diagram  (Figure  27),  at  the 
beginning  of  this  Chart.     See  that  cell  connections  are 
clean  and  tight.     Run  your  hand  along  each  wire  and 
feel  for  a  break  in  the  wire  under  the  insulation.    If  no 
such  break  can  be  found,  see  Section  C. 

C.  LAMPS   BURNED   OUT.     Inspect   the   lamps.     If 
they  are  all  good,  see  Section  D.     If  all  the  lamps  are 
burned  out,  it  is  probable  that  the  car  has  been  run  with 
the  battery  removed  without  taking  care  to  ground  the 
generator,  or  else  there  is  an  open  circuit  in  the  yellow 
wire  which  is  connected  to  the  starting  switch  at  one 
end  and  to  the  Ford  ammeter  at  the  other. 

Put  in  good  lamps.  If  they  all  burn  the  trouble  is  not 
due  to  an  open  circuit  in  the  yellow  wire  mentioned 
in  the  preceding  paragraph,  but  was  caused  by  running 
the  car  without  the  battery.  If  the  lamps  do  not  burn, 
take  an  extra  length  of  wire,  and  with  it  connect  to- 
gether the  terminal  on  the  starting  switch,  to  which  the 
yellow  wire  is  attached,  and  the  terminal  on  the  Ford 
ammeter  to  which  a  yellow  wire  is  also  attached  (See 
Figure  27).  If  this  causes  the  lamps  to  light,  there 
is  a  break  in  the  yellow  wire, 

G6 


CHAET  3 

To  determine  in  which  cable  the  break  exists,  hold  the 
extra  wire  between  the  Ford  ammeter  terminal  and  the 
second  terminal  from  the  left  on  the  terminal  block. 
If  the  lamps  now  light  the  break  is  in  the  cable  (shown 
at  D  in  Figure  21)  leading  from  the  ammeter  and  light- 
ing switch.  To  repair  it,  cut  outside  insulation  on  cable, 
separate  the  wires,  find  the  break  and  repair  it. 

If  the  lamps  did  not  light  up,  hold  the  extra  wire  on 
the  second  terminal  from  the  left  on  the  terminal  board, 
and  on  the  starting  switch  terminal  to  which  the  yellow 
were  is  attached.  If  the  lamps  now  light  up,  the  break  is 
in  the  cable  (shown  at  C  in  Figure  21)  which  runs  down 
the  right  side  of  the  terminal  block. 

D.  DEFECTIVE  LIGHTING  SWITCH.     With  a  short 
length  of  wire,  connect  the  "Bat"  terminal  on  the  back 
of  the  lighting  switch  to  the  "Head"  terminal,  then  to 
the  "Tail"  terminal,  then  to  the  "Aux"  or  "Dim"  ter- 
minal.    If  the  lamps  connected  to  these  terminals  light 
up  as  the  "Head",  "Tail",  and  "Aux"  or  "Dim"  terminals 
are  connected  to  the  "Bat"  terminal,  the  switch  is  de- 
fective, and  should  be  removed  and  opened  for  inspec- 
tion.   If  the  lamps  do  not  light  up  when  these  terminals 
are  connected  to  the  "Bat"  terminal,  see  Section  E. 

E.  OPEN  CIRCUIT  IN  LIGHTING  LINES.     Get  an 
extra  length  of  insulated  wire  about  6  feet  long.     Con- 
nect one  end  of  this  wire  to  the  terminal  on  the  start- 
ing switch  to  which  the  yellow  wire  is  connected.    With 
the  other  end  of  this  wire  touch  the  following  points  in 
the  order  in  which  they  are  named  below: 

(a)  Second  terminal  from  the  left  on  the  terminal 
block. 

If  lamps  now  light  up,  there  is  a  break  in  the  yel- 
low wire  between  the  starting  switch  and  terminal  block. 

(b)  Terminal  on  Ford  ammeter  to  which  yellow  wire 
is  connected. 

If  lamps  now  light  up,  there  is  a  break  in  the  yellow 

67 


CHART  3 

wire  between  the  terminal  board  and  the  Ford  ammeter. 

(c)  Other  terminal  on  the  Ford  ammeter. 

If  lamps  now  light  up,  there  is  a  break  in  the  Ford 
ammeter. 

(d)  "Bat"  terminal  on  back  of  lighting  switch. 

If  lamps  now  light  up,  there  is  a  break  in  the  wire 
connecting  the  Ford  ammeter  to  lighting  switch. 


68 


CHAET  4 


ENGINE  NOT  RUNNING 
LAMPS  ON 


FORD— CHART  4 
F.  A.  SYSTEM 


TO  BE  USED  IF  LAMPS  DRAW  TOO  MUCH 
CURRENT  FROM  BATTERY. 


TAIL.  U?  fe-  VOL-T 

BATTER.V 


-GREEN 
L-iGHTS  Be.  1QNITION  SW. 
OLD  TYPE    SWITCH 


FOR  D  -  "FA"  -  svsr  E  ivi 

CHART    3--4-S 


H'R  LAMP 


FIGURE  27. 


NOTE.  If  you  have  not  made  the  test  for  Engine  Not 
Running,  Lamps  Off,  do  so  now,  as  any  condition  which 
causes  a  discharge  reading  in  that  test  might  cause  an 
excessive  discharge  from  the  battery  in  this  test. 


69 


CHAET  4 

A.  EXTRA   EQUIPMENT   HAS  BEEN   ADDED.     If, 
upon  examination,  it  is  found  that  any  spot  light,  extra 
body  lamps,  trouble  lamps,  fuel  vaporizers,  hand  warm- 
ers on  the  steering  wheel,  cigar  lighters,  etc.,  have  been 
attached  to  the  car,  they  should  be  disconnected,  or  their 
switches  turned  off.    Only  the  original  factory  equipment 
of  lamps  should  be  used  for  this  test.    If  only  the  factory 
lamp  equipment  is  being  used  when  you  make  this  test, 
consult  section  B.    For  a  list  of  lamps  which  are  standard, 
see  below. 

The  factory  equipment  of  lamps  is  as  follows: 
Two — 6-8  volt,  17  candlepower  lamps  in  headlights. 
Two — 6-8  volt,     2  candlepower  lamps  in  headlights. 
One — 6-8  volt,     2  candlepower  lamp  in  taillight. 

B.  SHORT  CIRCUITS  OR  GROUNDS  IN  LIGHTING 
LINES— TEST.    Remove  all  the  lamps  from  their  sockets. 
Now  look  at  your  ammeter.    If  the  pointer  indicates  that 
current  is  still  flowing  from  the  battery,  there  is  trouble 
in  the  wires  leading  from  the  lighting  switch  to  the 
lamps. 

To  locate  this  trouble,  remove,  one  at  a  time,  the  wires 
from  the  "Head",  "Tail",  and  "Aux"  or  "Dim"  terminals 
on  the  back  of  the  lighting  switch.  As  each  wire  is  re- 
moved, look  at  your  ammeter,  and  if  the  pointer  goes  back 
to  the  "0"  line,  there  is  a  ground  or  short  circuit  in  the 
wire  which  caused  the  pointer  to  go  back  to  the  "0"  line 
when  you  removed  it. 


70 


CHART  5 


ENGINE  NOT  RUNNING 
LAMPS  ON 


FORD— CHART  5 

F.  A.  SYSTEM 


TO  BE  USED  IF  SOME  LAMPS  DO  NOT  LIGHT, 
OR  IF  SOME,  OR  ALL  LAMPS  BURN  DIMLY. 


TAH^LP          6  VOLT 
BATTERV 


FORD  -  FA'-SYSTEM 

CHART    3--4-S 


FIGURE  27.       • 

NOTE.  In  the  following  the  instructions  given  in  this 
chart,  read  those  paragraphs  the  heading  at  the  beginning 
of  which  describes  the  conditions  which  you  found. 

A.  IF  ALL  LAMPS  BURN  DIMLY— BATTERY 
TROUBLE.  Make  sure  that  the  battery  terminals  are 

71 


CHART  5 

free  from  dirt,  and  that  the  top  connectors  are  not  loose. 
If  any  corrosion  is  present,  clean  off  the  top  of  the  bat- 
tery with  a  rag  wet  with  ammonia  or  a  soda  solution. 
If  a  terminal  is  badly  corroded,  open  the  joint  if  possible 
and  scrape  off  the  corrosion  before  replacing-  the  cable. 
If  it  is  impossible  to  loosen  the  cable,  drill  off  the  ter- 
minal and  boil  it  in  soda  or  ammonia  solution.  If  this 
does  not  help  burn  on  a  new  terminal  and  cable. 

If  the  battery  is  clean  and  very  little  corrosion  is 
present,  measure  the  voltage  of  each  battery  cell.  If  one 
or  more  cells  show  little  or  no  voltage  it  is  "dead",  and 
the  battery  must  be  opened  for  repairs.  Complete  direc- 
tions for  doing  this  are  given  in  the  book  "The  Automo- 
bile Storage  Battery,  Its  Care  and  Repair",  published 
by  the  American  Bureau  of  Engineering. 

If  the  voltage  of  each  cell  measured  2  or  more,  see 
Section  B. 

B.  IF  SOME  OR  ALL  LAMPS  BURN  DIMLY  OR 
SOME  DO  NOT  LIGHT  UP— LAMP  TROUBLE. 

TEST :  Turn  the  defective  lamps  around  in  their  sockets 
to  make  sure  that  the  trouble  is  not  due  to  the  bulb  not 
making  good  contact  in  the  socket.  If  this  does  not  cause 
the  lamp  to  burn  brightly,  consult  the  following  remedy: 

REMEDY.  Look  for  the  following  trouble  in  the  de- 
fective lamps: 

(a)  Broken  or  burned  out  bulb. 

(b)  Double  contact  bulb  in  single  contact  socket. 

(c)  Contact  pieces  in  socket  too  short  to  make  con- 
tact with  the  contacts  on  the  lamp  base. 

(d)  Bulb  or  socket  contacts  dirty. 

(e)  Connectors   on   end   of   wires   supplying   current 
to  the  lamp  dirty,  or  not  making  contact  with  the  socket. 
Push  this  connector  piece  inward  and  turn  it  about  to 
make  sure  that  it  is  closing  the  circuit  to  the  socket. 

(f)  Bulbs  of  a  higher  voltage  than  8. 

.   72 


CHART  5 


(g)     Bulb  turned  the  wrong  way  in  socket, 
(h)     Loose,  dirty,  or  broken  wires  or  connections  in 
the  lamp  socket. 

(i)     Lamp  old,  and  almost  worn  out. 

C.  ALL  LAMPS  DIM— HIGH  RESISTANCE  BE- 
TWEEN BATTERY  AND  LIGHTING  SWITCH.  See 
that  the  terminal  connections  are  clean  and  tight.  Re- 
move any  oil,  dirt,  or  grease,  and  see  that  terminals  on 
wires  are  clean,  that  there  is  no  corrosion  at  the  soldered 
joint  between  the  wire  and  the  terminal  on  the  end  of 
the  wire,  and  that  none  of  the  wire  strands  are  cut 
through  at  the  terminal.  If  only  a  few  strands  are  un- 
broken, cut  the  wire  at  the  terminal  and  resolder  the 
wire  to  the  terminal. 

In  this  way  inspect  the  following  terminals: 

(a)  At  starting  switch  terminal  to  which  yellow  wire 
is  connected. 

(b)  At  terminal  block,  second  terminal  from  the  left 
as  you  face  the  terminal  block,  to  which  two  yellow  wires 
are  attached. 

(c)  Terminal  on  Ford  ammeter  to  which  yellow  wire 
is  attached. 

.  (d)     Other  terminal  on  Ford  ammeter. 

(e)     "Bat"   terminal   on   back   of   lighting   switch. 

If  you  do  not  find  any  trouble  at  these  terminals, 
and  cannot  make  the  lamps  light  up  properly  by  making 
terminals  clean  and  tight,  proceed  as  follows: 

Get  an  extra  length  of  wire,  about  6  feet  long.  At- 
tach one  end  of  it  to  the  starting  switch  terminal  to 
which  the  heavy  battery  cable,  and  the  yellow  wire  are 
connected.  (Leave  cable  and  yellow  wire  connected  to 
this  terminal  also.)  With  the  other  end  of  the  extra 
wire,  touch  the  following  terminals,  in  the  order  named: 

(a)  Terminal  on  terminal  block  to  which  two  yellow 
wires  are  connected. 

If  lamps  now  light  up,  there  is  a  partial  break  in  the 

73 


CHART  5 

yellow  wire  which  leads  from  the  terminal  block  to  the 
starting  switch.  If  this  cannot  be  found  by  inspection, 
cut  the  outside  braid  on  the  cable  which  is  at  the  right 
side  of  the  dash,  looking  at  the  dash  from  the  front  end 
of  the  car.  Look  for  the  partial  break  in  that  part  of 
the  yellow  wire  which  runs  in  this  cable. 

(b)  Terminal  on  Ford  ammeter  to  which  the  yellow 
wire  is  connected. 

If  lamps  now  light  up,  there  is  a  partial  break  in  the 
yellow  wire  which  connects  the  Ford  ammeter  to  the 
terminal  block.  If  this  cannot  be  found  by  inspection, 
cut  the  outside  braid  on  the  cable  which  contains  the 
wires  leading  from  the  terminal  block  to  the  Ford  am- 
meter and  lighting  switch.  Look  for  the  partial  break 
in  that  part  of  the  yellow  wire  which  was  enclosed  in 
this  cable. 

(c)  Other  terminal  on  Ford  ammeter. 

If  lamps  now  light  up,  there  is  a  loose  connection  in 
the  ammeter. 

(d)  "Bat"  terminal  on  lighting  switch. 

If  lamps  now  light  up,  there  is  a  partial  break  in  the 
wire  leading  from  the  Ford  ammeter  to  the  lighting 
switch. 

If  the  trouble  has  not  been  found  up  to  this  point,  see 
Section  D. 

D.  SOME  OR  ALL  LAMPS  DIM,  OR  SOME  LAMPS 
UNLIGHTED.  TROUBLE  IN  LIGHTING  SWITCH,  OR 
BETWEEN  LIGHTING  SWITCH  AND  LAMPS.  With 
the  end  of  the  same  wire  used  in  Section  C,  touch  the 
"Head",  "Tail"  and  "Aux"  or  "Dim"  terminals  on  the 
back  of  the  lighting  switch.  If,  when  you  touch  one  of 
these  terminals,  the  lamp  or  lamps  connected  to  this 
terminal  light  up,  there  is  a  loose  contact  connection  in- 
side the  switch,  and  the  switch  should  be  taken  apart 
and  loose,  dirty,  or  bent  contact  pieces  looked  for  and 
adjusted, 

74 


CHART  5 


If  lamps  do  not  light  when  you  touch  terminals  of 
switch,  the  trouble  must  lie  between  the  switch  and  the 
lamps.  It  may  be  in  the  wires  leading  to  the  lamps,  or  in 
the  ground  connection  at  the  lamp. 

Remove  the  connector  which  is  attached  to  the  lamp 
wires  in  back  of  the  light  containing  the  bulbs  which 
burn  dimly.  With  the  wire  which  you  have  been  using 
for  testing,  touch  the  terminals  in  that  part  of  the 
connector  which  is  in  the  reflector.  If  this  causes  the 
lamps  which  have  been  burning  dimly  or  have  not  been 
burning  at  all,  to  light  up,  the  ground  connection  at 
the  bulb  socket  is  defective  and  should  be  inspected  and 
put  in  working  order. 

If  lamps  do  not  light  up,  the  trouble  is  in  the  wires 
leading  from  the  lighting  switch  to  the  lamps,  and  if  it 
cannot  be  found  by  inspecting  those  portions  of  the  wires 
which  are  outside  the  cables,  cut  the  outside  braid  on 
these  cables  (see  C,  D,  and  E  in  Figures  20  and  21),  and 
look  for  the  trouble  inside  the  cable. 


CHART  6 


CHART  6— FORD  ENGINE  NOT  RUNNING 

F.  A.  SYSTEM  LAMPS  ON 

TO  BE  USED 

IF  AMMETER  IS  CONNECTED  UP  WRONG. 
If  ammeter  reads  backwards,  when  lamps  are  turned 
on,  reverse  the  wires  connected  to  the  meter. 


76 


CHAKT  7 


ENGINE  RUNNING 
LAMPS  OFF 


FORD— CHART  7 
F.  A.  SYSTEM 


TO  BE  USED  IF  BATTERY  IS  NOT  RECEIV- 
ING A  CHARGING  CURRENT. 


FIGURE  28. 
FOR  CARS  HAVING  CUTOUT  ON  DASH. 


AMMETER  CONNECTIONS.  Be  sure  to  reverse  the 
ammeter  connections  before  making  a  test  with  the  en- 
gine running,  and  the  lamps  turned  off. 

NOTE.  Sometimes  the  generator  may  be  made  to 
charge  the  battery  by  holding  the  cutout  contact  points 
together  for  an  instant,  and  then  forcing  them  open 
again,  or  by  short  circuiting  the  cutout.  If  the  points 

77 


CHART  7 


FORD 

AMMETER. 


CUTOUT 


INTERNAL  OF  <3ENE(?ATOR 
SEE    RIQURHS     €  Sc28   FOR  INTER- 
NAL. OF"  CUTOUT  SEC    FIGURE  24B 


FIGURE  28a. 
FOR    CARS    HAVING    CUTOUT    ON    GENERATOR. 


close  automatically  after  you  have  forced  them  open  by 
hand,  look  at  your  ammeter.  If  the  pointer  now  indicates 
that  the  battery  is  receiving  a  charging  current,  the  gen- 
erator is  now  working  properly. 

A.  LOCATING  THE  TROUBLE— TEST.  Get  an  extra 
length  of  insulated  wire  with  ends  bared,  not  smaller 
than  a  No.  12  in  size.  Connect  one  end  of  this  wire  to  the 
terminal  on  top  of  the  generator. 

If  the  cutout  is  mounted  on  the  dash,  remove  the  wire 
from  the  generator  terminal  before  attaching  the  extra 
wire. 

If  cutout  is  mounted  on  top  of  the  generator,  remove 
wire  from  cutout  before  attaching  the  extra  wire.  Con- 
nect the  other  end  of  the  extra  wire  to  the  terminal  post 

78 


CHART  7 


TO  LIGHT"  SWITCH 


WIRE    REMOVED  FROM  TERM- 
IMAL.  ON  TOP  OF  QEMEfeATDR 


<   rAMMETER 


EXTRA  WIREDESCRIBED    IN  SECTION  X"  OF    CHART 


TEST-  CONNECTIONS  TO  BE  MADE  AS  DESCRIBED 
IN  SECTION    X'Of=  CHART  *~7~  WHEN  CUTOUT  IS  MOUNTED   ON. 
THE  DASH 

FIGURE  29. 

on  your  ammeter,  to  which  you  already  have  connected 
the  wire  which  you  removed  from  the  positive  (+)  post 
on  the  battery  when  you  first  connected  in  your  ammeter, 
These  connections  are  shown  in  Figure  29  and  29a. 

Now  look  at  your  ammeter.  If  the  pointer  is  still 
over  the  "0"  line,  indicating  that  no  charging  current 
is  flowing,  or  if  the  pointer  goes  backward,  indicating 
that  the  battery  is  discharging  into  the  generator,  the 
generator  is  not  working  properly,  and  the  instructions 
given  in  Chart  9,  beginning  on  page  88,  should  be  fol- 
lowed. 


79 


CHART  7 


WIRE    RtMOVEt)    FROM  CUTOUT  TERMINAL 

~i^        TO  UI6HT    SWITCH 


EXTRA    WIRE    DESCRIBED   IN   SECTION   A   OF   CHART7 


6VOL.T    BATTERY 

SHOWING    TEST  CONNECTIONS  TO  BE    (vfADE   AS    DESCRIBED   IM  eECTION  >>"OF 
CHART  7  WHEN    CUTOUT  IS  MOUNTED  ON  TOP  OF  GENERATOR 

FIGURE  29a. 

If  the  pointer  on  the  ammeter  indicates  that  the  gen- 
erator is  now  charging  the  battery  at  10  amperes,  there 
is  a  break  in  the  circuit  between  the  generator  and  the 
battery,  and  the  following  instructions  should  be  fol- 
lowed. 


LOCATING  TROUBLE   OUTSIDE  THE  GENERATOR. 

B.  LOOSE  CONNECTIONS,  OR  BROKEN  WIRES. 
Disconnect  the  extra  wire  from  the  terminal  on  your 
ammeter.  The  other  end  of  the  extra  wire  should  still 
be  connected  to  the  terminal  on  the  generator.  With  the 
end  of  the  extra  wire,  which  you  removed  from  the  ter- 
minal on  your  ammeter,  touch  the  following  terminals, 
looking  at  your  ammeter  as  each  terminal  is  touched. 

(a)     "GEN"  TERMINAL  ON  CUTOUT.     (If  cutout  is 

80 


CHART 


mounted  on  the  dash).  If  your  ammeter  now  indicates 
generator  is  charging  battery,  examine  wire  leading  from 
generator  to  cutout  for  a  break.  This  break  may  be  un- 
der the  insulation.  If  your  ammeter  pointer  stays  over 
the  "0"  line,  see  (b). 

(b)  "BAT"   TERMINAL   ON   CUTOUT,   if   cutout   is 
mounted  on  the  dash.     "B"  terminal  on  cutout,  if  cut- 
out is  mounted  on  the  generator.    If  pointer  on  your  am- 
meter now  indicates  that  generator  is  charging  battery, 
see  Section  C. 

(c)  TERMINAL  ON  FORD  AMMETER  TO  WHICH 
TWO  WIRES  ARE   CONNECTED.     If  pointer  on  your 
ammeter  now  indicates  that  generator  is  charging  bat- 
tery, there  is  a  break  in  the  wire  connecting  the  cutout 
to  the  Ford  ammeter.     This  break  may  be  under  the  in- 
sulation, and  the  hand  should  be  run  along  the  wire  to 
feel  for  such  a  break. 

(d)  TERMINAL  ON  FORD  AMMETER  TO  WHICH 
A  YELLOW  WIRE  IS  CONNECTED.     If  your  ammeter 
now  indicates  that  generator  is  charging  battery,  there 
is  an  open  circuit  in  the  Ford  ammeter. 

(e)  TERMINAL  ON  TERMINAL  BLOCK  TO  WHICH 
TWO   YELLOW   WIRES   ARE    CONNECTED.      If   your 
ammeter  now  indicates  that  generator  is  charging  the 
battery,  there  is  a  break  in  the  yellow  wire  connecting 
Ford  ammeter  to  terminal  block.     Inspect  this  wire.     If 
no  break  can  be  found,  cut  outside  braid  on  cable  (shown 
at  D  in  Figure  21)  in  which  this  wire  runs  and  look  for 
break  in  that  portion  of  the  yellow  wire  enclosed  in  the 
cable  connecting  terminal  block  to  Ford  ammeter. 

(f)  If  your  ammeter  still  does  not  indicate  that  gen- 
erator is  charging  battery,  the  trouble  must  be  in  the 
yellow  wire  connecting  starting  switch  to  terminal  block. 
If  trouble  in  this  wire  cannot  be  found  by  inspection,  cut 

81 


CHART  7 


braid  on  cable  (shown  at  C  in  Figure  21)  in  which  the 
wire  runs  and  look  there  for  the  break. 

C.  CUTOUT  TROUBLE.  For  cutout  which  is  mounted 
on  the  dash.  Use  circuit  tester  shown  in  Figures  25  or 
26,  page  57.  Remove  the  wires  from  the  "Gen"  and  "Bat" 
terminals  on  cutout. 

(a)  CURRENT  COIL  OPEN  CIRCUITED. 

TEST:  Hold  one  test  point  on  "Bat"  terminal  on  cut- 
out, and  hold  other  on  stationary  contact  point  on  cutout 
shown  in  Figure  28  at  beginning  of  this  chart.  If  lamp 
does  not  light,  current  coil  is  open  circuited.  See  follow- 
ing "Remedy"  paragraph.  If  lamp  lights,  see  (b). 

REMEDY.  Put  in  new  cutout,  or  else  unwind  coils 
until  break  is  found,  repair  break  and  rewind  coils. 

(b)  VOLTAGE  COIL  OPEN  CIRCUITED. 

TEST:  Hold  one  test  point  on  "Gen"  terminal  on  cut- 
out. Hold  other  test  point  on  the  terminal  in  the  center 
between  the  "Gen"  and  "Bat"  terminals.  If  lamp  does 
not  light,  there  is  a  break  in  the  voltage  coil. 

REMEDY.  Install  new  cutout,  or  unwind  coils  until 
break  is  found,  repair  break,  and  rewind  coils. 

FOR  CUTOUT  MOUNTED  ON  TOP  OF  GENERATOR. 

Use  lamp  circuit  tester  shown  in  Figures  25  or  26,  page 
57. 

(a)     CURRENT  COIL  OPEN  CIRCUITED. 

TEST:  See  that  Screw  A  (see  Figure  24B)  is  not  miss- 
ing, as  this  would  open  the  charging  circuit.  If  screw  A 
is  in  place,  take  it  out  and  remove  the  cover  from  the  cut- 
out. Hold  one  test  point  on  piece  C,  and  hold  the  other 
test  point  on  piece  D.  If  lamp  lights  see  (b),  but  if  lamp 
does  not  light,  consult  the  following  "Remedy"  para- 
graph : 

82 


CHAET  7 


EEMEDY.  Carefully  inspect  the  soldered  connections 
between  pieces  C  and  D,  and  the  two  ends  of  the  current 
coil.  This  is  the  only  place  where  it  is  at  all  likely  that 
an  open  circuit  in  the  current  coil  may  be  found. 

(b)  VOLTAGE  COIL  OPEN  CIRCUITED. 

TEST:  Hold  one  test  point  on  the  base  of  the  cutout, 
and  hold  the  other  test  point  on  piece  H.  If  lamps  light, 
see  (c),  but  if  lamp  does  not  light,  consult  the  following 
"Remedy"  paragraph. 

REMEDY.  There  is  an  open  circuit  in  the  voltage 
coil.  Carefully  inspect  soldered  connections  between  the 
base,  piece  H,  and  the  ends  of  the  voltage  coil.  If  the 
connection  is  open,  or  wires  are  broken  near  the  joint, 
resolder  the  wires.  If  these  points  are  in  good  shape, 
the  break  is  inside  the  voltage  coil,  and  a  new  cutout 
should  be  installed,  or  else  the  coil  unwound,  repaired, 
and  then  unwound. 

(c)  OTHER  CUTOUT  TROUBLE.     In  either  style  of 
mounting,  a  short  circuit  in  the  voltage  coil  will  prevent 
the  cutout  from  closing.     If  no  cutout  trouble  has  been 
found,  replace  the  wires  on  the  cutout  and  short  circuit 
the  cutout  with  a  short  length  of  wire,  or  with  a  pair 
of  pliers.     If  this  gives  a  charging  current,  as  indicated 
on  your  ammeter,  the  voltage  coil  on  the  cutout  is  prob- 
ably short  circuited.     The  cutout  will  also  be  very  hot. 
A  ground  in  the  winding  would  have  the  same  effect  as 
a  short  circuit.     The  remedy  is  to  install  a  new  cutout, 
or  unwind  the  coils,  and  wind  a  new  voltage  coil,  using 
the  same  size  and  length  of  wire  found  in  the  defective 
voltage  coil. 

The  cutout  action  should  also  be  checked  according 
to  the  instructions  on  page  29. 


CHART  8 


CHART  8— FORD 
F.  A.  SYSTEM 


ENGINE  RUNNING 
LAMPS  OFF 


TO  BE  USED  IF  BATTERY  DISCHARGES  IN- 
STEAD OF  BEING  CHARGED. 


PORD 
AMMETER 


FIGURE  28. 
FOR  CARS  HAVING  CUTOUT  ON  DASH. 

NOTE.  Be  very  careful  to  have  your  ammeter  con- 
nected up  properly.  For  the  test  with  the  engine  run- 
ning, and  the  lamps  turned  off,  the  cable  which  you 
disconnected  from  the  positive  (+)  terminal  of  the  bat- 
tery must  be  connected  to  the  (+)  post  on  your  am- 
meter. The  "25"  or  " — "  post  on  your  ammeter  must  be 
connected  to  the  positive  (+)  terminal  of  the  battery. 
See  Figure  23. 

84 


CHART  8 


PORD 
AMMETER. 


-^f-  r-^^.  INTERNAL-  OF  GENERATOR 

/  SEE    RK5URES     6  Se28   F-OR  INTER- 

L-/ 1     NAl_  OF  CUTOUT  SEC    FISURE  Z4& 

FIGURE  28a. 
FOR    CARS    HAVING    CUTOUT    ON    GENERATOR. 

A.  TROUBLE  IN  WIRING.     Be  sure  that  you  have 
made  the  test  with  the  Engine  Not  Running  and  the 
lamps  turned  off.     Any  ground  between  battery  and  cut- 
out will  have  been  located  in  that  test. 

Inspect  the  wire  leading  from  the  cutout  to  the  gen- 
erator to  see  that  it  does  not  make  metallic  contact  with 
any  part  of  the  frame. 

B.  BATTERY     CONNECTIONS     REVERSED.       The 

negative  battery  terminal  should  be  connected  by  a  short 
cable  to  the  frame  of  the  car.  Be  sure  that  the  positive 
is  not  connected  to  the  frame  of  the  car  instead  of  the 
negative. 

C.  GENERATOR    REVERSED— TEST.      Use    a   volt- 
meter as  shown  in  Figure  30.    Hold  one  test  point  on  a 


CHART  8 


VOLTMETER 


TO  CUTOUT 


GENERATOR  TERIY1INAL- 


MEASURING 


VOLTAGE  OF  GENERATOR 

FIGURE  30. 


clean  spot  on  the  dynamo  frame  (the  rear  hearing  oiler 
will  do).  Hold  the  other  test  point  on  the  generator 
terminal.  The  voltmeter  pointer  should  show  a  voltage 
of  about  7  to  7y2.  If  the  pointer  moves  backward  the 
polarity  of  the  dynamo  is  reversed. 

REMEDY.  This  can  only  happen  when  the  battery  is 
run  down.  Put  in  a  fully  charged  battery  and  hold  the 
cutout  closed  by  hand  for  an  instant.  Then  look  at  your 
ammeter  to  see  if  generator  is  charging  battery.  If  bat- 
tery is  still  discharging,  reverse  field  connections  in  gen- 
erator. To  do  this  interchange  the  field  wires  which  are 
connected  to  the  third  brush  and  the  grounded  main 
brush. 


86 


CHART  9 


ENGINE  RUNNING 
LAMPS  OFF 


FOED— CHAET  9 
F.  A.  SYSTEM 


TO  BE  USED  IF  BATTERY  IS  NOT  RECEIV- 
ING  ENOUGH    CHARGING    CURRENT. 


FORD 
AMMETER 


FIGURE  28. 
FOR  CARS  HAVING  CUTOUT  ON  DASH. 


NOTE.  Try  closing  cutout  by  hand  for  an  instant  and 
then  opening  it.  The  same  result  may  be  obtained  by 
short-circuiting  the  cutout.  If  it  then  closes  automatically 
and  generator  begins  to  charge  battery  at  10  amperes,  the 
trouble  has  been  removed.  If  generator  is  charging  about 
8  amperes,  someone  may  have  changed  the  setting  of 
the  third  brush.  For  adjusting  third  brush,  see  page  14. 

87 


CHART  9 


PORD 

AMMETER. 


CUTOUT 


FOR  INTERNAL  OF  GENERATOR 
SEE    PIQURBS     6  Bf  23   FOR  INTER- 


FIGURE  28a. 
FOR  CARS  HAVING  CUTOUT  ON  GENERATOR. 

If  charge  is  less  than  8  amperes,  carry  out  the  following 
instructions. 

A.  LOCATING  THE  TROUBLE.  To  determine 
whether  the  trouble  is  in  the  generator,  or  between  the 
generator  and  the  battery,  make  the  test  described  in 
Chart  7,  on  page  78, 

LOCATING  GENERATOR  TROUBLES. 

NOTE.  Generator  field  takes  about  2.5  amperes  when 
connected  to  a  6  volt  battery  if  field  is  0.  K.  Generator 
runs  as  motor  takes  9  amperes  from  a  6  volt  battery  if 
there  are  no  shorts  or  grounds  in  armature,  and  if  field  is 
0.  K 

88 


CHART  9 

B.  TROUBLE     IN     THE     DRIVING     MECHANISM. 
Watch  the  dynamo  shaft  while  the  engine  is  running  to 
see  that  it  turns  smoothly  and  continuously  and  in  the 
proper  direction.     Run  the  engine  at  various  speeds.     If 
the  dynamo  shaft  follows  the  changes  in  the  speed  of 
the  engine  closely  and  runs  in  the  proper  direction,  the 
driving  mechanism  is   working  properly   and  section   C 
should  be  consulted. 

If  the  armature  alternately  runs  and  stops,  or  runs 
irregularly,  or  in  the  wrong  direction,  the  driving  mech- 
anism is  not  working  properly  and  should  be  put  in  good 
shape  before  proceeding  farther. 

The  driving  mechanism  is  described  on  page  4. 

C.  LOOSE,     GROUNDED,     OR    SHORT    CIRCUITED 
WIRES  AND  CONNECTIONS.     Remove  the  cover  from 
the  rear  end  housing.    See  page  17  and  Figures  1  and  5. 
Look  in  through  the  openings  in  the  housing  and  inspect 
the  wire  leading  from  the  terminal  on  the  generator  to 
the  ungrounded  main  brush  and  the  wires  leading  from 
the   field   coils  to   the   third  brush   and  grounded  main 
brush.     See   that   the   insulation  on  these  wires  is  not 
torn  or  cut  at  any  point.    See  that  the  pigtails  connected 
to  the  brushes  do  not  touch  the  end  housing  or  brush 
ring.     The  pigtails  may,  of  course,  be  allowed  to  touch 
the  brush  holders. 

D.  WATCH  FOR  EXCESSIVE  SPARKING  AT  THE 
BRUSHES.     This  may  be  due  to : 

(a)  Brushes  of  poor  material,  or  replaced  with  wrong 
size  or  type. 

(b)  Armature   loose,    or   carried   eccentrically  in   its 
bearings. 

(c)  Brushes  not  bearing  on  the  proper  points  of  the 
commutator.    The  whole  brush  ring  may  be  shifted  as  de- 
scribed on  page  11. 

(d)  Short  circuited,  grounded,  or  open  circuited  coil 
in  the  armature.     This  sparking  will  occur  only  as  the 

89 


CHART  9 


commutator  segments  to  which  the  coils  are  connected 
pass  under  a  brush.  If  two  adjacent  segments  are  black- 
ened or  burned,  it  almost  invariably  indicates  a  short 
circuit  between  the  windings  connected  to  these  two  seg- 
ments. 

For  tests  to  locate  short  circuits  and  open  circuits,  see 
Section  G. 

Any  of  the  above  troubles  will  cause  insufficient  charg- 
ing current. 

The  trouble  given  in  next  section  may  also  cause  spark- 
ing. 

E.  BRUSH  TROUBLE.  The  brushes  are  reached  by 
removing  the  cover  from  the  end  housing.  To  inspect 
the  under  side  of  the  brushes,  take  a  pair  of  long  nosed 
pliers  and  pull  upon  the  pigtail  at  the  brush.  The  brush 
may  he  removed  and  inspected  in  this  way. 

Stop  the  engine  and  examine  the  brushes  for  the  fol- 
lowing trouble: 

(a)  Dirty,    pitted   or   broken   contact  surface. 

(b)  Insufficient   contact   surface.     The   parts   of   the 
brush  surface  that  makes  contact  with  the  commutator 
will  look  smooth  and  polished,   while   other  parts  will 
look  dull  and  rough.     In  either  (a)  or  (b),  if  the  brush 
contact  surface  is  not  perfect,  cut  a  piece  of  fine  sand- 
paper a  little  wider  than  the  brush  and  insert  it  between 
the  brush  and  the  commutator  with  the  sanded  side  to- 
ward the  brush.     Draw  the   sandpaper  back  and  forth 
under  the  brush  so  that  the  smooth  side  of  the  sandpaper 
follows  the  surface  of  the  commutator  closely.    When  all 
imperfections  in  the  brush  surface  have  been  removed, 
remove  the  sandpaper  and  carefully  wipe  away  all  carbon 
dust  which  may  have  fallen  on  the  commutator. 

(c)  Brushes   too   short   to   give   satisfactory   contact 
surface  should  be  replaced  with  new  ones  obtained  from 
the  car  makers. 

(d)  Improper  spring  tension.     See  that  the  springs 
are  not  broken  or  loose  from  the  brush,  or  the  brush 

00 


CHAET 9 


stuck  in  the  holder. 

(e)  Defective  insulation.  Broken,  cut  or  cracked  in- 
sulating washers  or  bushings  should  be  replaced  with 
new  ones.  Remove  any  dirt,  grease  or  gummy  substance 
from  the  brushes  and  brush  holders  with  a  stiff  hair 
brush  soaked  in  gasoline.  After  putting  the  brushes  in 
good  shape,  make  another  test  for  Engine  Running, 
Lamps  Off,  after  running  the  engine  for  about  twenty 
minutes  to  "seat"  or  "run  in"  the  brushes.  If  the  gen- 
erator now  gives  a  10  ampere  charge  no  further  work 
need  be  done.  If  the  charge  rate  is  still  too  low,  stop  the 
engine  and  consult  section  F. 

F.     COMMUTATOR  TROUBLE. 

(a)  DIRTY.     A  commutator  that  is  in  good  condi- 
tion has  a  polished  brownish  or  purple  appearance.     If 
there  is  any  dirt  or  grease  on  it,  clean  it  by  holding  a 
rag  moistened  with  gasoline  against  it  while  the  engine 
is  running.    In  a  similar  way,  remove  any  dirt  from  the 
contact  surfaces  of  the  brushes. 

(b)  HIGH  MICA,  OR  HIGH,  LOW,  OR  ROUGHENED 
SEGMENTS.     If  any  segments  are  higher  or  lower  than 
adjacent  ones,  or  have  grooves  caused  by  uneven  wear- 
ing, or  if  any  mica  is  flush  with,  or  projects  above  the 
surface  of  the  segments,  and  if  cleaning  the  commutator 
did  not   cause   a  normal  charging  current,   remove  the 
dynamo  from  the  car  and  place  the  armature  in  a  lathe 
and  take  off  a  fine  cut.     Then  undercut  the  mica.    If  a 
lathe  is  not  available,  smooth  the  commutator  with  fine 
sandpaper  and  then  undercut  the  mica. 

To  undercut  the  mica,  use  a  piece  of  hack  saw  blade, 
the  sides  of  whose  teeth  have  been  ground  off  until  they 
will  cut  a  slot  slightly  wider  than  the  mica.  With  this 
tool,  cut  away  the  mica  until  it  is  below  the  surface 
of  the  segments  by  about  1/32  of  an  inch.  To  start 
the  cut,  draw  the  end  of  the  saw  blade  lightly  along 
the  mica  so  as  to  make  a  scratch  on  it.  Gradually  en- 
large this  scratch  until  the  blade  may  be  drawn  along 

91 


CHART  9 


the  mica  vigorously  without  slipping  upon  the  segments. 
After  undercutting  the  mica,  the  edges  of  the  segments 
should  be  beveled  slightly  with  a  three  cornered  file  in 
order  to  remove  any  burrs  caused  by  the  saw  blade. 

Be  sure  to  get  all  the  mica  cut  to  the  desired  depth, 
especially  those  pieces  next  to  the  segments.  If  possible, 
use  a  small  magnifying  glass  to  determine  whether  you 
have  removed  all  the  mica.  Do  not  use  a  sharp  pointed 
tool  in  this  work,  as  this  will  simply  make  a  V  shaped 
groove  and  will  not  remove  those  pieces  next  to  the 
segments. 

G.  COMMUTATOR  AND  ARMATURE  WINDING 
TROUBLE.  The  best  device  for  locating  short  circuits, 
grounds,  open  circuits,  and  crossed  connections  in  any 
sized  armature,  no  matter  whether  it  is  one  inch  or  20 
feet  in  diameter,  and  of  any  voltage,  using  only  one 
ampere  of  test  current,  is  the  Ambu  Armature  Tester. 
This  Tester  may  be  used  on  any  test  supply  circuit,  either 
D.  C.  or  A.  C.,  and  having  any  voltage  from  6  to  220. 
A  less  sensitive  test  is  given  below. 

(a)  OPEN  CIRCUITS  OR  SHORT  CIRCUITS— TEST. 
Take  a  single  dry  cell  in  good  condition,  and  attach  two 
wires  to  its  terminals.  Connect  one  post  on  the  cell  to 
one  terminal  of  your  ammeter  and  connect  a  wire 
to  the  other  terminal  on  your  ammeter.  The  free  ends 
of  the  wire  connected  to  the  terminal  on  your  ammeter 
and  the  second  post  on  the  cell  are  to  be  used  as  the 
test  points.  The  ends  of  these  lines  may  be  fitted  with 
testing  points  or  may  simply  be  twisted  so  that  there  are 
no  loose  strands.  See  Figure  31. 

To  make  a  test,  the  brushes  should  be  raised  from  the 
commutator.  Starting  at  any  point  on  the  commutator, 
rest  the  test  points  on  adjacent  segments  and  quickly 
note  the  approximate  reading  on  the  scale  of  your  am- 
meter. In  this  way  take  a  reading  between  each  pair 
of  adjacent  segments  all  the  way  around  the  commutator, 
but  do  not  allow  the  test  points  to  rest  on  the  segments 

92 


CHART  9 


AMMETER 


USE  ONE  DRY   CEI_L-  OR 
ONE   CEL.L-  OFT  STORAQE 
BATTER  V 


THESE   WIRES   SHOULD  BE  HEAVY 


-HOLD    TEST  POINTS  ON  SEGMENTS 
IAN02,   2AWP2^    SAND-^  «4ANPS,  AMD 
SO    ON 


TESTING    ARMATURE     FOR    SHORT  CIRCUITS, 
CIRCUIT'S    AND  GROUNDS 

FIGURE  31. 


OPEN 


any  longer  than  absolutely  necessary  to  note  the  approxi- 
mate reading.  If  the  commutator  and  armature  are  free 
from  short  circuits  and  open  circuits,  the  reading  between 
each  pair  of  segments  will  be  about  the  same  all  the 
way  around.  In  case  the  reading  becomes  much  greater 
with  the  test  points  resting  on  any  pair  of  segments,  it 
indicates  that  the  segments  being  touched,  or  the  arma- 
ture coil  attached  to  these  segments  is  short  circuited. 

93 


CHART  9 

In  case  the  reading  becomes  very  much  less,  it  indicates 
a  broken,  burned  out,  or  otherwise  open  circuited  arma- 
ture coil  between  the  two  segments  on  which  the  test 
points  are  then  resting. 

REMEDY.  If  an  open  circuit  exists,  see  that  the  wires 
leading  from  the  segments  make  good  contact  with  the 
latter,  and  are  not  broken  as  far  as  they  can  be  traced. 
If  no  trouble  can  be  found,  the  winding  must  be  unwound 
until  the  trouble  is  found  and  repairs  made. 

If  a  short  circuit  exists,  remove  any  bits  of  metal  or 
carbon  which  may  have  lodged  in  the  mica  between  the 
slots.  To  remove  dirt  use  a  stiff  brush  or  a  bellows.  If 
any  segments  have  been  damaged  so  that  the  copper 
touches  the  next  segments,  cut  the  metal  away  so  that 
the  segments  are  clear  from  one  another.  If  this  does 
not  eliminate  the  trouble,  as  shown  by  another  test  for  a 
short  circuit,  the  short  circuit  is  in  the  armature  wind- 
ings, and  if  it  cannot  be  found  by  inspection,  the  wind- 
ing must  be  taken  apart  until  the  trouble  is  located  and 
repairs  made. 

(b)  GROUNDED— TEST.  Insulate  the  brushes  from 
the  commutator  with  pieces  of  dry  paper.  Using  a  cir- 
cuit tester  as  described  on  page  57,  Figures  25  or  26, 
hold  one  test  point  on  the  frame  of  the  dynamo  and 
hold  the  other  test  point  on  the  commutator.  If  the  lamp 
lights,  there  is  a  ground  in  the  commutator  or  armature 
windings. 

REMEDY.  Look  for  broken  wires,  or  loose  strands 
which  may  cause  a  ground.  Remove  any  grease,  dirt  or 
moisture  from  the  segments.  If  the  ground  cannot  be 
be  eliminated  in  this  way,  remove  the  wires  from  the 
segments,  and  repeat  the  test  for  a  ground.  If  the 
trouble  still  remains,  the  commutator  itself  is  grounded 
and  should  be  reinsulated.  If  the  ground  has  disappeared, 
the  trouble  is  in  the  winding,  and  if  it  cannot  be  found 
by  inspection,  the  winding  must  be  removed  until  the 
trouble  is  found  and  repairs  made. 


CHART  9 


DRV  RAPE  R  _2^ 
UNDER.  BRUSHES 


FIELD  WIRE    DIS- 
CONNECTED   FROM 
GROUNDED    BRUSH 

TESTING    FIELP  COIL-S   FOR  OPEN  CIRCUITS 
FIGURE  32. 

H.  SHUNT  FIELD  TROUBLE.  In  order  to  test  the 
fields,  remove  the  end  housing.  (See  directions  page  17, 
and  Figures  3  and  4.)  Do  not  disconnect  the  wire  which 
is  attached  to  the  third  brush  holder.  Disconnect  the 
wire  from  the  grounded  main  brush  holder.  Use  a  cir- 
cuit-tester as  shown  on  page  57,  Figures  25  or  26. 

(a)  OPEN  CIRCUIT— TEST.  Put  pieces  of  dry  paper 
under  the  third  and  both  main  brushes.  Hold  one  test 
point  on  third  brush  holder,  and  hold  other  test  point 
on  the  wire  removed  from  the  grounded  main  brush 
holder.  See  Figure  32,  If  lamp  lights,  see  paragraph 
(b).  If  lamp  does  not  light,  see  following  remedy. 

REMEDY.  There  is  an  open  circuit  in  the  field  coils. 
Inspect  carefully  the  joints  in  the  connections  between 
field  coils.  These  joints  should  be  well  soldered.  If 
these  joints  are  all  in  good  shape,  unwind  the  tape  from 

95 


CHART  9 


6V.  LAMP 


.<o  VOLT 
/  PATTER' 


HOLD  TEST  POINTS  ON 
PLACES    MARKED    1,2,3,4-, 
5,  IN   FOLLOWING    ORDER 
1  AND  2^  2  AND  3,   ZAN04--4AND5 


FIELD  WIRE  DI&- 
CONNECTED    FROM 
GROUNDED    BRUSH 


DRY  PAPER 
UNDER    BRUSHES 


REMOVE   IN&UL.ATION 
FROM  FIELD  WIRE 
AND  HOLD  TEST  POINT 
ON  THE  BAKE    WIRE  . 
DO  THIS  BETWEEN  EACH 
PAIR  OF  FIELD  COILS 


TESTING   EACH^FIEL-D  COIL.  FOR    OPEN  CIRCUIT 
FIGURE  33. 

them.  Then  test  each  field  coil  for  open  circuit  by  hold- 
ing the  test  points  on  the  bare  ends  of  the  coil.  See  Fig- 
ure 33.  Each  good  coil  will  cause  the  lamp  to  burn 
when  tested  in  this  way.  If  lamp  does  not  burn  when 
any  coil  is  tested  in  this  way,  that  coil  is  open  cir- 
cuited. 

Remove  the  defective  field  coil.  To  do  this,  take  out 
the  screw  which  holds  the  pole  piece  in  place.  Remove 
pole  piece.  Disconnect  field  coil  from  the  others  and 
then  remove  it.  If  you  cannot  find  any  break  in  the 
coil  by  inspection,  unwind  the  coil  carefully  until  you 
find  the  break.  Repair  break  and  replace  the  coil. 

(b)     GROUND—  TEST.    Use  same  circuit  tester.    Hold 


96 


HOLD  THIS    TEST 
POINT  ON  MAIN 
FRAME  OF  SENEfeA- 

TOR,  BUT  NOT  ON  END 
HOUSING  IN  WHICH 

BRUSHES 
MOUMTED 


DRY  PAPER 
UNDER   BRUSHES 


TESTJNQ    FIELD  COIL^FOR  GROUND 

FIGURE  34. 

one  test  point  on  the  third  brush  and  hold  the  other  test 
point  on  any  part  of  the  main  frame.  See  Figure  34. 
(Not  the  end  housing.  This  housing  should  not  be 
touching  generator  frame,  or  any  other  metal  part). 
If  the  lamp  lights,  there  is  a  ground  in  the  field  coils, 
and  you  should  consult  the  following  "Remedy"  para- 
graph. If  the  lamp  does  not  light,  hold  the  test  point 
which  you  were  holding  on  the  generator  frame  on 
the  end  housing.  If  the  lamp  now  lights  the  third 
brush  holder  is  grounded  to  the  end  housing,  and  you 
should  consult  the  following  "Remedy",  Now  hold  one 

97 


CHART  9 


6  VOLT  LAMP 


o- 


THIS  TEST   POINT  TO 
BE  HELD  SUCCESSIVELY 
ON     1,2,  3,  AND  4 


HOt_D  THIS    TEST 
POINT  ON   MAIN 
FRAME  OF=  GENERA- 
TOR  FOR  ENTIRE  TEST 


STORAGE    BATTERY 


DRY 
UNDER  BRUSHES 


DISCONJME 


ECT   FIELD  COILS   FROM   ONE  ANOTHER. 
TESTING    EACH  FIELD  COIL.    FOR  GROUND 

FIGURE  35. 

test  point  on  the  insulated  main  brush  holder  and  hold 
the  other  test  point  on  the  end  housing.  If  lamp  lights, 
consult  following  "Remedy."  If  lamp  does  not  light,  see 
paragraph  (c). 

REMEDY.  IF  THE  LAMP  LIGHTED  WHEN  YOU 
HELD  ONE  TEST  POINT  ON  THE  THIRD  BRUSH,  AND 
THE  OTHER  TEST  POINT  ON  THE  MAIN  FRAME  OF 
THE  GENERATOR,  there  is  a  ground  in  the  field  coils. 
Carefully  inspect  the  connections  between  the  field  coils 
for  damaged  insulation  which  allows  the  bare  field  wire 

98 


CHART  9 

NEITHER    BATTERV  TERMINJAL  MUST    BE    GROUNDED 


AMMETER    READINGS 
UP  TO  25  AMPERES 


POINTED     BRASS  RODS  USED 
AS  TEST  POINTS 


MAKING  A  CIRCUIT  TESTER  WITH  AN  AMMETER 
FIGURE  36. 

to  touch  the  main  generator  frame.  If  no  ground  can 
be  found  in  this  way,  it  will  be  necessary  to  disconnect 
the  field  coils  from  each  other  by  unsoldering  the  joints 
between  them.  Then  test  each  coil  separately  by  hold- 
ing one  test  point  on  the  main  generator  frame,  and  with 
the  other  test  point  touch  one  after  another,  the  wires 
leading  to  the  coils.  See  Figure  35.  If  lamp  lights  when 
any  coil  is  tested  in  this  way,  that  coil  is  grounded.  Re- 
move coil  as  directed  in  (a)  above,  and  carefully  inspect 
it  for  any  damaged  insulation.  If  you  cannot  find  any, 
unwind  the  coil  carefully  until  the  damaged  insulation 
is  found.  Repair  insulation  and  rewind  coil. 

IF  LAMP  LIGHTED  WHEN  YOU  HELD  ONE  TEST 
POINT  ON  THE  END  HOUSING  OF  GENERATOR  AND 
WITH  THE  OTHER  TEST  POINT  TOUCHED  THE 
THIRD  BRUSH  HOLDER,  OR  THE  INSULATED  MAIN 
BRUSH  HOLDER,  the  third  brush  holder,  or  the  insu- 
lated main  brush  holder  is  grounded.  Remove  brush  ring 
as  directed  on  page  17,  and  inspect  the  insulation  under 

99 


CHART  9 


HOLD  TEST    POINTS    ON    BARE 
FIELD  WIRES  AT   F=-OLLOWIN<5 
PLACES  1ANDZ.,   2  AMD  3,  25ANJD-4 
4ANDS.     AT  THESE     PLACES  THfc 
INSULATION    SHOULD    BE.  RE- 
MOVED   FROM  WIRES 


DRY    PAPER 
UNDER,   BRUSHES 


TESTING    FIELD  COIL-S    FOR    SHORT   CIRCUIT 
FIGURE  37. 

the  third  brush  holder  and  main  brush  holder  to  which 
the  wire  from  the  generator  terminal  is  connected.  Look 
for  any  damaged  part  which  allows  brush  holder  to  make 
metallic  contact  with  brush  ring,  or  which  allows  brush 
ring  to  make  metallic  contact  with  end  housing. 

(c)     SHORT  CIRCUIT— TEST.     Use  a  circuit  tester 
as  shown  in  Figure  36,    Test  each  coil  by  holding  test 


100 


CHAET  9 


STORAGE    BATTERY 


COMPASS 


TESTING    FOR   REVERSED   REUD 
COIL..    SUCCESSIVE    POl_ES  MUST 

ATTRACT  OPPOSITE     ENDS    OP 

COMPASS    NEEDUE 


FIGURE  38. 


points  on  the  two  bare  ends  of  the  wire  of  the  coil.  See 
Figure  37.  Note  what  current  is  indicated  by  your  am- 
meter as  you  test  each  coil.  With  a  6-volt  battery,  each 
coil  should  take  about  10  amperes.  If  any  coil  takes 
more  than  10  amperes  when  tested  in  this  way,  that 
coil  is  short  circuited,  and  the  following  "Remedy"  should 
be  consulted.  If  each  coil  takes  only  10  amperes,  consult 
paragraph  (d). 

REMEDY.     Remove,  inspect,  and  repair  defective  coil 
as  already  explained. 

(d)     ONE  FIELD  COIL  REVERSED— TEST.     For  this 


101 


CHAET  9 


test  you  will  need  a  compass.  Any  small  pocket  compass 
will  do.  Connect  the  two  end  field  wires  (that  are  ordi- 
narily attached  to  the  third  brush  holder,  and  grounded 
main  brush  holder)  to  a  6-volt  battery.  See  Figure  38. 
Hold  the  compass  right  side  up  in  your  hand  about  one 
foot  away  from  generator  frame.  Now  gradually  bring 
compass  toward  one  of  the  screws  which  hold  the  field 
poles  in  place.  As  the  compass  is  brought  near  this  screw, 
one  end  of  the  compass  needle  will  be  attracted  and  will 
point  directly  at  this  screw.  Now  move  compass  straight 
out  from  generator  until  it  is  about  one  foot  away.  Then 
bring  compass  toward  the  next  screw  holding  a  field  pole 
in  place.  As  the  compass  is  brought  near  this  second 
screw,  the  other  end  of  the  compass  needle  should  be 
attracted  and  should  point  at  this  second  screw.  Test 
the  next  two  field  poles  in  the  same  way.  Each  field  pole 
screw  should  attract  the  opposite  end  of  the  compass  needle 
that  the  previous  pole  did.  See  Figure  38.  If  three  suc- 
cessive poles  attract  the  same  end  of  the  compass  needle, 
the  middle  one  of  these  poles  which  you  tested  is  con- 
nected wrong,  and  the  connections  to  it  should  be  reversed. 

I.  GENERATOR  TERMINAL  GROUNDED.  The  insu- 
lation around  the  generator  terminal  has  given  trouble 
by  cracking  and  allowing  generator  terminal  to  become 
loose.  If  this  terminal  is  loose  it  may  become  grounded 
to  the  generator  frame.  Inspect  this  insulation  carefully. 
If  it  is  broken  or  cracked,  so  as  to  allow  the  terminal  to 
touch  the  frame,  put  in  new  insulation. 


102 


CHAET  10 


ENGINE  RUNNING 
LAMPS  OFF 


FORD— CHART  10 
F.  A.  SYSTEM 


TO  BE  USED  IF  GENERATOR  CHARGES  BAT- 
TERY AT  MORE  THAN  10  AMPERES. 


FORD 

AMMETER 


FIGURE  28. 
FOR  CARS  HAVING  CUTOUT  ON  DASH. 


NOTE.  The  high  charging  current  may  be  necessary 
on  account  of  peculiar  driving  conditions.  If  the  car 
is  driven  much  at  night,  or  if  the  starting  motor  is  used 
often,  10  amperes  may  not  keep  the  battery  charged. 
Find  out  carefully  whether  the  battery  runs  hot  while 
engine  is  running,  and  if  it  is  necessary  to  add  water 
oftener  than  usual.  If  this  is  the  case,  the  charging 

103 


CHART  10 


BATTERY 
FORD 

AMMETER. 
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CHARTS  7-S-9-IO 

^     /    ^          FOR  INTERNAL.  OF  GENERATOR 
/                 SEE    Rie,USTES     6  8c28    POR   INTER- 
—  /  NAL   OP   CUTOUT  SEE     FIGL/RTE.   Z'JB 

CUTOU-r 

FIGURE  28a. 
FOR  CARS  HAVING  CUTOUT  ON  GENERATOR. 


rate  should  be  decreased.  If,  however,  battery  does  not 
run  hot,  or  water  does  not  have  to  be  added  too  often,  the 
high  charging  rate  need  not  be  decreased. 

For  directions  to  increase  or  decrease  the  charging  rate, 
see  page  14. 


104 


CHAET  11 


FORD— CHAET  11 
F.  A.  SYSTEM 

TO  BE  USED  IF  YOUR  AMMETER  POINTER 
JUMPS  AROUND  ALL  OVER  THE  SCALE  OR 
IS  OTHERWISE  UNSTEADY. 

A.  LOOSE    CONNECTIONS    IN    LIGHTING    LINES. 
If  the  pointer  jumps  while  the  engine  is  not  running, 
look  for  loose  or  broken  wires,  loose  or  dirty  connections, 
loose  switch  contacts,  etc.,  in  the  line  from  the  battery 
and  generator  to  the  lighting  circuits. 

B.  TROUBLE  IN  LAMPS.    If  the  pointer  jumps  only 
with  certain  lamps  turned  on,  look  for  loose  or  broken 
wires,    loose    or    dirty    connections,    short    circuits,    or 
grounds  in  the  lines  to  these  lamps,  and  in  the  connec- 
tions at  the  lamp  bases,  or  for  loose  lamp  bulbs.     The 
lamps  in  whose  circuits  the  trouble  exists  will  nicker. 

C.  TROUBLE  IN  GENERATOR.    If  the  charging  cur- 
rent is  unsteady,  look  for  the  following  troubles: 

(a)  FAULTY  DRIVING  MECHANISM.     Watch  the 
shaft  at  the  dynamo  while  the  engine  is  running.     Run 
the  engine  at  various  speeds,   and  if  the  dynamo  does 
not  run  smoothly,  but  alternately  starts  and  stops,   or 
if  its  speed  does  not  change  with  that  of  the  engine,  the 
driving  mechanism   is   at   fault,   and   sheared  keys   and 
broken  drive  gear,  should  be  looked  for. 

(b)  BRUSHES  AND  CONNECTIONS.     Examine  the 
brushes  and  their  holders  and  see  that  the  contact  surfaces 
on  the  brushes  are  clean  and  smooth,  that  the  brushes  are 
not  loose  in  the  holders,  that  the  springs  are  not  loose, 
broken  or  weak  and  that  they  make  good  contact  with  the 
brushes,  and  that  the  pigtails  leading  from  the  brushes 
make  good  contact. 

(c)  COMMUTATOR.    Examine  the  surface  of  the  com- 
mutator for  dirt  or  grease,  high,  low  or  loose  segments, 

105 


CHART  11 

insulation  sticking  up  between  the  segments,  for  loose  or 
broken  wires  leading  from  the  segments,  and  for  bits  of 
metal  or  carbon  on  the  insulation  between  segments. 

(d)  LOOSE  OR  BROKEN  WIRES.    Look  for  loose  or 
broken,  or  crossed  wires  inside  the  generator.    See  that  the 
generator  terminal  is  clean  and  tight. 

(e)  OTHER  TROUBLE.     Consult  Chart  9,  beginning 
page  92,  and  make  the  tests  for  grounds,  open  circuits 
and  short  circuits  in  the  field  coils  and  armature.    Exam- 
ine  the   cutout  to   see   that  neither  spring  is  loose   or 
broken,   that  the  contact  points  are  clean  and  smooth, 
that  the  arm  moves  freely  and  does  not  bind  at  the  pivot. 

D.  TROUBLE  IN  THE  CHARGING  LINE.  If  the 
charging  current  is  unsteady  after  making  the  above 
tests,  follow  the  charging  lines  and  look  for  loose,  dirty 
connections,  broken  wires,  and  defective  insulation  which 
may  cause  intermittent  short  circuits  or  grounds. 


106 


CHART  12 


STARTING  TROUBLE 


FORD— CHART  12 
F.  A.  SYSTEM 


TO  BE  USED  IF  STARTING  MOTOR  DOES  NOT 
CRANK  ENGINE  SATISFACTORILY. 


€>  VOL-T 
BATTE  RY 


STARTING 
SWITCH 


FORD  *FA'  SYSTEM. 
CHART-  12 


FIGURE  39. 


A.  MECHANICAL  TROUBLE— TEST.  Crank  the  en- 
gine by  hand  to  make  sure  that  it  will  start.  If  it  starts, 
see  paragraph  B,  but  if  it  will  not  start,  consult  the  fol- 
lowing remedy: 

REMEDY.  There  may  be  ignition  or  carburetor 
trouble,  or  some  parts  of  the  power  plant  may  be 

107 


CHART  12 


binding  from  overheating,  lack  of  lubrication,  some  ac- 
cident may  have  caused  damage,  the  transmission  gears 
may  be  in  mesh,  or  some  other  purely  mechanical  trouble 
may  be  present. 

B.  NOTE.     Having  determined  that  the  engine  will 
start  when  cranked  by  hand,  if  the  motor  will  not  crank 
the  engine,  or  starts  it  too  slowly  to  start  the  engine, 
make  the  tests  for  Engine  Not  Running,  Lamps  Off;  En- 
gine  Not   Running,    Lamps    On;    and   Engine    Running, 
Lamps  Off;  before  proceeding  with  the  work  of  this  chart. 
To  make  the  test  for  Engine  Running,  Lamps  Off,  it  will 
be  necessary  to  crank  the  engine  by  hand.    If  the  reading 
in  each  of  the  above  tests  is  not  correct,  follow  the  in- 
structions given  in  the  proper  charts.     If  this  does  not 
make  the  starter  action  satisfactory,  consult  Section  C. 

C.  HIGH    RESISTANCE    IN    CIRCUIT    BETWEEN 
BATTERY  AND  MOTOR.     Inspect  carefully  the  battery 
for  corroded  connections  or  loose  terminals  or  connecting 
straps.      Inspect    entire    cable    leading   from   battery   to 
starting  motor.     Inspect  terminal   connections  at  start- 
ing switch  and  motor.     Clean  and  tighten  all  terminals 
that  need  it.     See  that  there  is  no  looseness  or  corrosion 
at  the  lugs  soldered  to  the  starting  motor  cable.     If  no 
trouble  is  found  in  this  way,  hold  a  length  of  heavy  wire 
across  the  two  terminals  on  the  starting  switch.     If  this 
causes  starting  motor  to  crank  engine  satisfactorily,  the 
starting  switch  is  defective.     Open  switch  and  look  for 
loose  dirty,  or  bent  parts  which  should  be  put  in  good 
shape. 

D.  GROUND  BETWEEN  STARTING  SWITCH  AND 
MOTOR.     As  a  ground  in  the  starting  motor  cable  be- 
tween the  starting  switch  and  the  battery  would  have 
been  discovered  in  the  test  for  Engine  Not  Running,  if 
there  is  any  ground  in  the  starting  cable,  it  must  be  be- 
tween  the   switch   and   the   motor.      Inspect   this   caMe 

108 


CHAET  12 


carefully  to   make   sure   its  insulation  is  not   damaged 
so  as  to  allow  cable  to  touch  metal  parts  of  car. 

E.  LOW   VOLTAGE    OR    OPEN    CIRCUIT   IN   BAT- 
TERY.    Remove,  one  at  a  time,  the  battery  cables  at- 
tached to  the  battery.    Scrape  away  any  dirt  or  corrosion 
with  a  knife,  and  then  clean  the  contact  surfaces  on  the 
cables  and  battery  posts  with  fine  sandpaper.     Replace 
the  cables  and  screw  them  firmly  into  place.    After  mak- 
ing all  battery  connections  clean  and  tight,  see  if  the 
motor  will  now  crank  the  engine.     If  not  see  next  para- 
graph. 

TEST  NO.  1.  With  the  starting  switch  open,  measure 
voltage  of  battery.  Should  the  indication  be  less  than  6 
volts,  measure  the  voltage  for  each  cell.  If  any  cell 
should  show  less  than  two  volts,  or  no  voltage  at  all, 
look  for  loose,  dirty,  broken  or  corroded  terminal  con- 
nections on  top  of  the  battery. 

TEST  NO.  2.  With  the  starting  switch  closed,  again 
measure  the  voltage  of  the  battery,  as  directed  in  Test 
No.  1.  If  the  voltage  now  drops  to  a  very  low  value, 
consult  test  No.  3.  If  the  voltage  in  this  test  is  about  5, 
proceed  with  section  F. 

TEST  NO.  3.  With  a  hydrometer,  measure  the  gravity 
of  each  cell  of  the  battery.  The  gravity  should  not  be 
less  than  1.250  for  any  cell.  If  any  cell  shows  a  gravity 
which  is  much  less  than  the  others,  consult  the  chapter 
in  the  Ambu  Battery  Book  headed  "What  is  the  Trouble". 
If  all  cells  show  low  gravity,  the  car  has  not  been  run 
long  enough  in  the  day  time  to  keep  the  battery  charged, 
some  trouble  has  been  causing  a  leakage  of  current,  the 
dynamo  has  not  been  delivering  sufficient  charging  cur- 
rent, or  else  there  is  trouble  in  the  battery  as  described 
in  the  Trouble  Charts  in  the  Ambu  Battery  Book.  If  the 
starter  action  is  still  unsatisfactory,  consult  Section  F. 

F.  TROUBLE  IN  THE   STARTING   MOTOR.     Make 
the  tests  on  the  brushes,  commutator  and  armature,  de- 

109 


CHART  12 

scribed  in  Chart  9,  beginning  page  90,  paragraphs  E,  F 
and  G.  In  addition,  make  the  tests  described  below,  on 
the  motor  fields. 

Use  a  lamp  circuit  tester  as  shown  on  page  57,  Figures 
25  or  26.  The  starting  motor  field  coils  are  made  of 
heavy  copper  conductors.  The  ends  of  the  coils  are  not 
taped  up  (See  Figure  14),  and  the  bare  copper  should 
be  inspected  carefully  to  see  that  none  of  it  touches  the 
main  motor  frame. 

(a)  GROUND — TEST.     If  no   ground  is  found,   put 
pieces  of  paper  under  the  brushes  so  as  to  insulate  them 
from  the  commutator.     Now  hold  one  test  point  on  the 
terminal  on  the  motor.    Hold  the  other  test  point  on  the 
frame  of  the  motor.    If  lamp  does  not  light,  see  (b)  be- 
low.    If  lamp  lights,  see  the  following  "Remedy." 

REMEDY.  There  is  a  ground  in  field  circuit.  Dis- 
connect one  at  a  time,  the  two  large  insulated  field  wires 
from  the  two  insulated  motor  brush  holders.  Repeat 
above  test  as  each  of  these  wires  is  removed.  If  lamp 
goes  out  after  one  of  these  wires  is  removed,  the  brush- 
holder  to  which  that  wire  is  attached  is  grounded  to  the 
brush  ring,  and  must  be  reinsulated. 

If  lamp  still  burns  after  both  wires  are  removed  from 
the  brushes,  the  ground  is  in  the  field  coils  of  the  motor. 
This  may  be  located  by  disconnecting  each  field  coil  and 
testing  each  one  separately.  When  the  lamp  lights  up 
when  certain  field  coil  is  tested  (by  holding  test  points 
on  motor  frame,  and  end  wire  of  coil),  that  field  coil  is 
grounded.  Remove  and  repair  coil  as  already  directed  for 
generator  field  coils. 

(b)  OPEN  CIRCUIT.     It  is  very  unlikely  that  one 
of  the  motor  field  coils  is  open  circuited.     The  soldered 


110 


CHART  12 

joint,  between  coils  should,  however,  be  inspected  care- 
fully to  see  that  joint  is  well  soldered. 

To  test  for  open  circuit,  open  the  joint  between  any 
two  field  coils.  Use  lamp  circuit  tester  as  shown  on  page 
57,  Figures  25  or  26.  Test  each  coil  by  holding  the 
test  points  on  the  bare  ends  of  each  coil.  If  lamp  does 
not  light  as  one  of  the  coils  is  tested  in  this  way,  that 
coil  is  open  circuited  and  should  be  removed  and  repaired 
as  already  directed  for  the  generator  field  coils. 

G.  DRIVE  TROUBLE,  BENDIX  TYPE.  The  driving 
parts  between  the  armature  shaft  and  flywheel  gear 
should  be  examined  as  follows : 

(a)  The  screw  shaft  must  be   clean  and  free  from 
grease  and  dirt. 

(b)  The  spring  which  fastens  the  screw  shaft  sleeve 
to  the  extension  of  the  armature  shaft  should  be  unbroken 
and  tightly  bolted. 

(c)  The  small  pinion  should  be  clean,  the  teeth  should 
be  smooth,  and  it  should  be  possible  to  rotate  the  pinion 
freely  on  the  screw  shaft. 

(d)  The   flywheel   gear   teeth   should  be   clean   and 
smooth.     If  they  are  burred,  they  should  be  filed  until 
roughness  is  removed. 


Ill 


FORD  IGNITION  SYSTEM 

GENERAL, 

Ford  cars  which  are  equipped  with  the  F.  A.  Starting 
and  Lighting  System  retain  the  standard  Ford  magneto 
and  the  vibrator  coils  on  the  dash.  The  storage  battery 
may  be  used  for  ignition  also,  but  should  only  be  used 
when  starting  the  engine,  and  in  case  of  the  magneto 
failing.  A  circuit  diagram  of  the  ignition  circuits  is 
shown  in  Figure  40.  See  page  43  for  path  taken  by  ig- 
nition current.  The  switching  from  battery  to  magneto, 
or  magneto  to  battery  is  done  with  the  ignition  key  in 
the  lighting  switch.  When  this  key  is  turned  toward 
"Bat",  the  Ford  magneto  is  cut  out  and  the  battery  (or 
generator  if  car  is  running)  is  then  used  for  ignition. 
When  the  key  is  turned  to  the  "Mag"  position,  the  Ford 
magneto  is  used  for  ignition. 

THE  FORD  MAGNETO.  This  magneto  is  of  a  unique 
construction,  having  been  designed  especially  for  the 
Ford  car.  It  consists  essentially  of  two  parts,  one  of 
which  remains  stationary,  and  the  other  of  which  ro- 
tates. The  stationary  part  consists  of  sixteen  coils  or 
spools  of  copper  ribbon  as  shown  in  Figure  40  wound  on 
short  iron  cores.  The  cores  are  mounted  on  an  iron 
plate,  through  which  the  magnetic  circuit  between  spools 
is  completed.  Adjacent  coils  have  their  copper  ribbon 
wound  around  the  cores  in  opposite  directions.  One  end 
of  the  set  of  coils  is  connected  to  a  terminal  block  at  the 
top,  the  magneto  terminal  which  projects  through  the 
top  of  the  flywheel  case  making  contact  with  this  ter- 
minal block.  The  other  end  of  the  set  of  coils  is  con- 
nected to  the  iron  base  plate  upon  which  the  spools  are 
mounted. 

The  rotating  part  of  the  Ford  magneto  consists  simply 
of  a  set  of  16  permanent  magnets  mounted  on  brass, 
which,  in  turn  is  fastened  to  the  flywheel.  Each  magnet 
is  a  magnetized,  II  shaped,  steel  bar.  These  magnets 
are  placed  as  shown  in  Figure  41.  In  mounting  these 
magnets,  like  poles  of  adjacent  magnets  are  placed  to- 
gether, That  is,  the  north  pole  of  any  magnet  is  placed 

113 


FOED  IGNITION  SYSTEM 


COMMUTATOR. 


FIGURE  40. 


next  to  the  north  pole  of  the  next  magnet  on  one  side, 
and  the  south  pole  of  the  magnet  is  placed  next  to  the 
south  pole  of  the  adjacent  magnet  on  the  other  side  of  it. 
In  placing  the  magnets  in  this  manner,  the  magnetic  cir- 
cuit of  the  magnets  is  left  incomplete,  since  the  like 

113 


FOED  IGNITION  SYSTEM 


poles  of  the  adjacent  magnets  repel  each,  other,  and  lines 
of  force  cannot  pass  from  one  magnet  to  the  next. 

The  magnets  rotate  with  the  flywheel,  their  ends  pass- 
ing very  close  to  the  iron  cores  of  the  spools  of  copper 
ribbon.  The  lines  of  force  from  the  magnets  pass  through 
these  cores  and  the  iron  plate  from  which  the  cores  are 
mounted,  thus  completing  the  magnetic  circuit.  The  lines 
of  force  passing  through  the  spools  generate  the  voltage 
N 


Kl 


N 


MAGNETS   OF    FORD    MA6NETO 
FIGURE  41. 


of  the  magneto.  The  voltage  in  each  spool  alternates, 
or  reverses  in  direction  every  time  a  different  magnetic 
pole  is  opposite  the  spool.  Suppose  at  a  certain  instant, 
the  north  poles  of  a  pair  of  the  magnets  is  opposite  the 
core  of  any  spool.  The  lines  of  force  will  then  go  from 
the  magnets  and  into  the  spool.  The  next  poles  on  the 
magnets  are  south  poles,  and  when  they  are  opposite 
the  spool,  the  lines  of  force  go  from  the  spool  and  into  the 

114 


FORD  IGNITION  SYSTEM 


VIBRATOR 

VIBRATOR  ARM 

\    VIBRATOR,    CONTACT    POINTS 

\  /      rCJ3-1_AIRaAP  ADJUSTMENT 

V     \        _  /         i 

CONNECTS  TO 
COMMUTATOR 


TERMINAL.    CLIPS    FOR  THE  4-  COIUS   ARE 
AL.U  CONNECTED   TO  MERE 

FOf?D    IGNITION  COIL.  UNIT 
FIGURE  42. 

magnets,  which  is  the  reverse  of  the  direction  taken  by 
the  lines  of  force  when  the  north  poles  of  the  magnets 
are  opposite  the  spool.  The  Ford  magneto  therefore, 
generates  an  alternating  voltage,  and  the  current  flowing 
in  the  magneto  circuits  is  also  alternating,  or  one 
whose  direction  is  reversed  regularly  as  the  engine  ro- 
tates. 

HOW  TO  REMOVE  FORD  MAGNETO,    In  order  to  re- 
115 


FORD  IGNITION  SYSTEM 

move  the  Ford  magneto,  it  is  necessary  to  remove  the  en- 
gine. When  this  has  been  done  remove  crank  case  and 
transmission  cover.  Take  out  four  cap  screws  which  hold 
flywheel  to  crankshaft.  Mark  parts  properly  to  facilitate 
reassembling. 

When  assembling  magnets  and  lining  up  magneto, 
take  care  that  faces  of  magnets  are  just  1/32  inch  away 
from  surface  of  core  of  spools. 

FORD  DASH  COILS.  The  Ford  Ignition  coils  contained 
in  the  coil  box  on  the  dash  consist  of  four  separate  units 
which  are  enclosed  in  wooden  boxes.  Each  unit  is  merely 
slipped  into  place,  electrical  contact  being  made  between 
three  round  contact  plates  or  buttons,  and  spring  con- 
tact clips  fastened  to  the  terminals  on  the  outside  of  the 
box.  The  construction  and  arrangement  of  one  of  the 
coil  units  are  shown  in  Figure  42. 

The  only  attention  that  the  coils  need  is  cleaning  and 
keeping  adjusted  the  vibrator  contact  points.  If  these 
are  dirty,  clean  them  by  drawing  between  them  a  rag 
moistened  with  kerosene.,  If  they  are  rough,  they  should 
be  made  smooth  with  a  flat,  fine  toothed  file,  having  filing 
surface  on  both  sides.  When  the  vibrating  arm  is  held 
down,  the  distance  between  the  contact  points  should  be 
slightly  less  than  1/32  inch.  If  it  differs  from  this,  it 
should  be  adjusted.  To  do  this,  loosen  the  top  one  of 
the  nuts  on  the  top  vibrator  arm  (see  Figure  42),  and 
then  turn  bottom  nut  to  bring  air  gap  to  correct  length. 
Then  turn  down  top  nut  again  and  lock  the  bottom  nut 
in  place.  All  adjustment  must  be  made  with  these  two 
nuts  and  not  by  bending  the  arms  which  carry  the  con- 
tact points. 

It  is  important  that  the  vibrators  be  properly  adjusted. 
This  does  not  mean  that  the  adjustment  should  be  tink- 
ered with  continually.  Once  the  proper  adjustment  is 
made,  the  vibrator  should  not  be  touched  again  unless 

116 


TKOUBLES  IN  THE  POWER  PLANT 

absolutely  necessary  in  order  to  put  in  new  contact 
points,  or  reduce  the  air  gap  when  it  becomes  too  great 
on  account  of  the  points  wearing  down. 

COMMUTATOR.  The  commutator  completes  the  cir- 
cuit of  each  ignition  coil,  when  the  piston  in  the  cylin* 
der  whose  spark  plug  is  connected  to  that  coil  is  in  the 
firing  position.  It  consists  of  a  roller  which  runs  on  the 
inside  of  a  ring  which  has  four  contacts  embedded  in 
insulating  material.  The  roller  is  mounted  on  a  shaft 
which  is  driven  by  a  gear  mounted  on  the  main  engine 
shaft.  This  gear  also  drives  the  F.  A.  generator.  The  rol- 
ler rotates  at  half  the  speed  of  the  engine.  As  the 
roller  comes  in  contact  with  each  metal  segment,  or  con- 
tact piece  mentioned  above,  the  circuit  of  the  ignition 
coil  which  is  connected  to  that  segment  is  completed. 
The  vibrator  of  this  coil  then  begins  to  act,  and  a  high 
voltage  is  induced  in  the  high  tension  secondary  winding 
of  that  coil.  This  voltage  is  high  enough  to  cause  a 
spark  to  pass  between  the  points  of  the  spark  plug  which 
is  connected  to  this  winding. 

HOW  TO  REMOVE  COMMUTATOR.  1.  Detach  spark 
rod  from  commutator  by  taking  out  the  cotter  pin. 

2.  Release  the  spring  which  bears  on  the  commutator 
case  by  loosening  nut  on  breather  pipe  which  holds  the 
spring  in  place.  Case  may  then  be  removed. 

IGNITION  AND  ENGINE  TROUBLES.  When  every 
part  of  the  power  plant  is  doing  its  work  properly,  there 
will  be  a  steady  purring  sound  from  the  exhaust.  If 
there  is  any  trouble  which  affects  the  action  of  the  en- 
gine, this  steady  purring  sound  will  not  be  heard.  Most 
troubles  are  indicated  and  may  be  detected  by  sound. 
There  are  certain  symptoms  by  which  trouble  is  indicated, 
and  this  trouble  may  or  may  not  lie  in  the  ignition  sys- 
tem. In  order  to  determine  whether  the  ignition  system 

117 


TROUBLES  IN  THE  POWEE  PLANT 

is  at  fault,  certain  tests  must  be  made.     These  will  be 
described  later. 

The  symptoms  which  always  are  signs  of  trouble  are : 

1.  ENGINE  REFUSES  TO  START. 

2.  ENGINE  STARTS,  BUT  ONE  OR  MORE  CYLIN- 
DERS DO   NOT  FIRE.     THIS  FAILURE  TO  FIRE  IS 
CALLED  MISSING. 

3.  BACKFIRING,     OR     EXPLOSION     OF     CHARGE 
WHILE  PISTON   IS  TRAVELING   UPWARD  ON  THE 
COMPRESSION  STROKE. 

4.  POUNDING,    OR    ABNORMAL   NOISES    IN    THE 
ENGINE,  USUALLY  CALLED  "KNOCKING". 

5.  ENGINE  IS  WEAK,  AND  DOES  NOT  DEVELOP 
FULL  POWER. 

6.  ENGINE  GRADUALLY  LOSES  POWER. 

7.  IRREGULAR  ACTION  OF  ENGINE. 

Each  of  the  above  troubles  may  be  due  to  the  fuel  sys- 
tem, the  ignition  system,  or  may  be  in  the  cylinders. 

1.     ENGINE  REFUSES  TO  START. 

A.  FUEL  SYSTEM.     Gasoline  tank  empty.     Gasoline 
line  shut  oif.     Water  in  gasoline.     Gasoline  supply  line 
choked  up.    Dirt  in  carburetor  float  base.    Engine  flooded 
with  gas  on  account  of  continual  turning  over  with  car- 
buretor air  choke  closed.     Carburetor  float  stuck.     Car- 
buretor needle  valve  closed.     Gasoline  not  vaporizing  in 
cold  weather. 

B.  ENGINE.    Air  leak  in  intake  manifold.    Poor  com- 
pression.    Water  in  cylinder  because  of  leak  in  water 
jacket.    Valves  not  timed  properly. 

C.  IGNITION.    If  you  tried  to  start  on  the  magneto, 
turn  the  ignition  key  over  to  the  "Bat"  position.     If 
engine  now  starts,  trouble  is  in  magneto. 

MAGNETO  CONTACT  SPRING.     If  ignition  is  weak 

118 


TROUBLES  IN  THE  POWER  PLANT 

when  running  on  magneto,  but  strong  when  running  on 
battery,  the  trouble  may  be  due  to  dirt  under  the  mag- 
neto contact  spring  which  is  held  in  place  by  the  binding 
post  on  top  of  crankcase.  To  examine  this  spring,  re- 
move the  screws  in  base  of  binding  post.  You  can  then 
remove  the  binding  post  and  spring  and  clean  out  any 
dirt. 

TESTS  ON  FORD  MAGNETO  COILS.  First  take  out 
the  coils.  To  test  them,  proceed  as  follows: 

(a)  OPEN  CIRCUIT— TEST.     Use  lamp  circuit  tester 
as  shown  on  page  57,  Figures  25  or  26.     Hold  one  test 
point   on  terminal  block  and  hold  other  test  point   on 
plate  on  which  coils  are  mounted.    If  lamp  does  not  light, 
there  is  an  open  circuit. 

REMEDY.  Carefully  inspect  connection  from  terminal 
block  to  coil,  and  from  next  coil  (to  the  right)  to  the 
plate  on  which  coils  are  mounted.  Then  inspect  all  con- 
nections between  coils.  If  no  trouble  is  found  in  this 
way,  scrape  some  insulation  from  all  the  connections  be- 
tween coils.  Test  each  coil  by  holding  test  points  on 
successive  bare  spots,  similar  to  the  method  shown  in 
Figure  33.  Defective  coil  will  not  cause  lamp  to  light 
and  should  be  unwound  until  break  is  found.  Repair 
break  and  carefully  rewind  coil. 

(b)  GROUND.     Remove  ground  connection  of  right 
hand  top  coil  from  plate  on  which  coils  are  mounted. 
Hold  one  test  point  on  terminal  of  left  hand  top  coil 
and  hold  other  test  point  on  plate  on  which  coils  are 
mounted.    If  lamp  lights,  there  is  a  ground  in  one  of  the 
coils. 

REMEDY.  Carefully  inspect  all  coils  for  cut,  torn, 
or  oil  or  water  soaked  insulation.  If  none  can  be  found, 
disconnect  one  coil  at  a  time  from  the  other  coils  and 
test  it  for  ground  until  the  grounded  coil  is  found.  Then 
unwind  and  reinsulate  defective  coil  and  rewind. 

(c)  SHORT  CIRCUIT.    Use  an  ammeter  circuit  tester 

119 


TEOUBLES  IN  THE  POWER  PLANT 

as  shown  on  page  99,  Figure  36.  Scrape  insulation  from 
connections  between  coils.  Test  each  coil,  in  a  manner 
similar  to  that  shown  on  page  100,  Figure  37.  If  any  coil 
takes  much  more  current  than  the  others,  it  is  short-cir- 
cuited. Unwind,  reinsulate,  and  rewind  defective  coil. 

(d)  REVERSED    COILS— TEST.      Connect   a  battery 
to  the  wires  connected  to  the  two  top  coils.     Test  each 
coil  by  bringing  a  compass  towards  it.     Successive  coils 
should  attract  opposite  ends  of  the  compass  needle,  similar 
to  Figure  38.     If  two  or  three  successive  coils  attract 
same  end  of  compass  needle,  the  second  or  middle  coil  is 
reversed.    It  may  be  necessary  to  reverse  this  and  all  the 
remaining  coils.    This  should  be  tested  with  the  compass. 

(e)  TESTING  MAGNETO  TERMINAL  FOR  GROUND, 
The  wire  should  be  disconnected  from  the  terminal.    The 
terminal  must  also  be  insulated  from  the  coil  connection 
inside  the  magneto.     Use  lamp  circuit  tester  as  shown 
on  page  57,  Figures  25  or  26.     Hold  one  test  point  on 
terminal,  and  hold  other  test  point  on  frame  of  engine. 
If  lamp  lights,  the  magneto  terminal  is  grounded  and 
should  be  taken  off  and  reinsulated. 

TESTING  COMMUTATOR.  If  engine  still  refuses  to 
start,  trouble  is  in  coils,  commutator,  or  wiring.  Look 
first  inside  the  commutator.  See  that  roller  and  segments 
on  inside  of  ring  are  clean  and  free  from  grease.  Remove 
dirt,  oil,  or  grease  with  a  rag  wet  with  gasoline.  Make 
all  parts  smooth  with  fine  sandpaper.  See  that  roller 
spring  is  not  loose  or  broken,  preventing  roller  from  mak- 
ing contact.  See  that  roller  revolves  and  touches  each 
contact  segment  as  engine  is  turned  over. 

TESTING  DASH  COILS.  If  no  trouble  is  found  in 
commutator,  turn  to  the  coils.  Remove  the  wires  from  the 
upper  row  of  binding  posts  on  the  back  of  the  coil 
units.  Switch  the  ignition  to  the  battery.  With  a 
screwdriver,  pliers,  or  short  length  of  wire,  short  cir- 

120 


TKOUBLES  IN  THE  POWEE  PLANT 

cult  each  of  the  binding  posts  in  the  top  row  to  the 
rod  which  supports  the  radiator,  or  short  circuit  thein 
to  any  part  of  the  engine.  As  each  binding  post  is  short 
circuited  to  the  engine  or  radiator  rod,  the  coil  conected  to 
that  post  should  buzz.  If  one  or  more  do  not  buzz,  or  if  all 
of  them  do  not  buzz,  remove  the  coil  units  and  examine 
the  three  contact  buttons  on  each  coil  unit.  See  that 
these  are  clean  and  smooth.  See  that  the  spring  contact 
clips  which  are  attached  to  the  back  of  the  binding  posts 
are  not  bent  or  missing.  See  that  vibrator  points  are 
smooth,  clean  and  adjusted  as  previously  described. 

The  common  terminal  (see  Figure  42)  is  connected  to 
the  brass  strip  which  extends  across  the  bottom  of  the 
coil  box.  This  connection  sometimes  comes  loose.  Test 
this  with  the  lamp  circuit  tester  shown  on  page  57,  Fig- 
ures 25  or  26.  Hold  one  test  point  on  the  common  ter- 
minal, and  hold  the  other  on  the  brass  strip  in  the  bot- 
tom of  the  coil  box.  If  the  lamp  does  not  light,  the  con- 
nection between  the  brass  strip  and  the  common  ter- 
minal is  broken.  The  break  will  probably  be  found  in 
the  soldered  joints  located  at  the  back  of  the  common 
terminal,  or  in  the  center  (approximately)  of  the  strip  in 
the  bottom  of  the  coil  box. 

If  trouble  has  not  yet  been  found,  test  each  coil  unit 
with  the  lamp  circuit  tester.  Remove  each  unit  to  test 
it. 

(a)  Test  across  (that  is,  hold  the  test  points  on  the 
two  places  mentioned)  contact  buttons  A  and  B.    If  lamp 
does  not  burn,  test  with  voltmeter  circuit  tester  as  shown 
in  Figure  43.     If  voltmeter  pointer  does  not  move,  high 
tension  winding  is  open  circuited. 

(b)  Test  across  contact  button  C  and  arm  on  top  of 
coil  which  carries  stationary  vibrator  contact  point.     If 
lamp  does  not  light,  low  tension  winding  is  open  cir- 
cuited. 

(c)  Put  card  or  paper  between  vibrator  points.    Then 
test  across  stationary  and  movable  vibrator  points.     If 

121 


TROUBLES  IN  THE  POWER  PLANT 

NEITHER    BATTERY  TERMINAL  MUST  BE,  GROUNDED 

A  DRY  CELLS  IN  SER  IES  MAY  BE  USED 
INSTEAD  OF  THE    STORAGE    BATTERS 


VOLTMETER    READING 
UPTD  IO  VOLTS 


POINTED    BRASS  RODS  USED 
AS    TEST    POINTS 


MAKING  A  CIRCUIT  TESTER    WITH  A 
VOLTMETER 

FIGURE  43. 

lamp  lights,  these  two  vibrator  points  are  short-circuited 
to  each  other.  The  short  circuit  may  be  in  the  wires 
which  are  connected  to  these  vibrator  points,  or  the  pri- 
mary and  secondary  windings  may  be  short-circuited. 

(d)  Remove  wires  from  commutator.  Test  between 
each  wire  removed  and  the  other  wires  carried  in  the 
same  cable.  The  other  ends  of  these  wires  must,  of 
course,  be  removed  from  the  coil  box.  If  lamp  lights  up 
as  any  pair  of  wires  is  tested  in  this  way,  these  two 
wires  are  short  circuited  to  each  other.  Cut  outside  braid 
on  cable  and  examine  wires.  Find  defective  insulation 
and  repair  it.  The  insulation  on  this  cable  is  sometimea 
destroyed  by  oil  leaking  on  it,  and  gradually  dissolving 
the  rubber  in  the  insulation. 

2.     ENGINE  STARTS,  BUT  ONE  OR  MORE  CYLINDERS 

MISFIRE. 
To  determine  whether  trouble  is  in  fuel  or  ignition  sys- 


122 


TEOUBLES  IN  THE  POWER  PLANT 

terns,  or  in  engine,  test  as  follows : 

Stop  engine  and  turn  it  over  by  hand.  If  compression 
is  weak  in  any  cylinder,  that  cylinder  is  causing  the 
misfiring.  If  compression  is  good  on  all  cylinders,  the 
trouble  must  be  in  fuel  system  or  ignition  system.  The 
color  of  the  exhaust  will  help  some  in  determining  in 
which  system  trouble  is  located. 

Colorless  exhaust  with  no  backfire,  indicates  ignition 
trouble. 

Black  smoke  at  exhaust  indicates  too  rich  a  gasoline 
mixture. 

Blue  smoke  indicates  color  in  cylinder  or  oil  supply  sys- 
tem. 

If  trouble  seems  to  be  in  ignition  system,  locate  missing 
cylinder  as  follows: 

Run  the  engine  throttled  down.  Take  a  screwdriver 
which  has  a  thoroughly  insulated  wooden  handle.  Hold 
tip  of  screwdriver  on  top  of  engine  near  the  spark  plug. 
Bring  shank  of  screwdriver  up  against  terminal  on  top 
of  spark  plug.  This  will  short  circuit  the  plug  and  cut 
out  that  cylinder.  If  this  makes  no  difference  in  the 
sound  of  the  engine,  and  engine  does  not  slow  down,  you 
have  found  the  cylinder  which  is  at  fault.  If  there  is  a 
marked  difference  in  sound  of  engine,  and  engine  slows 
down,  you  are  testing  a  live  cylinder  and  you  have  not 
found  the  faulty  cylinder.  You  should  then  test  each 
cylinder  until  you  find  the  faulty  one,  as  indicated  by 
no  difference  in  sound  of  engine  when  you  short  circuit 
the  plug. 

Another  method  of  locating  missing  cylinder  is  as  fol- 
lows: 

Open  throttle  slightly.  Remove  cover  from  coil  box 
on  dash.  Hold  down  three  of  the  vibrators.  By  holding 
down  these  vibrators  you  kill  the  ignition  in  the  cor- 
responding cylinders.  If  the  engine  now  stops,  the  re- 
maining cylinder  is  the  faulty  one  If  engine  still  runs 
the  remaining  cylinder  is  firing  properly.  Hold  down 

123 


TROUBLES  IN  THE  POWER  PLANT 


three  vibrators  at  a  time  in  the  following  order,  until 
engine  stops  when  three  are  held  down:  (a)  2,  3,  4. 
(b)  1,  3,  4.  (c)  1,  2,  4,  (d)  1,  2,  3. 

Some  men  prefer  to  hold  down  only  one  vibrator  at 
a  time  and  note  the  effect  on  the  engine.  If  engine  slows 
down,  the  cylinder  corresponding  to  the  vibrator  which 
is  being  held  down  is  a  live  one.  If  engine  does  not  slow 
down,  the  cylinder  is  the  dead  one.  Having  located  the 
fanlty  cylinder,  take  the  screwdriver  again.  Hold  the 
tip  of  the  screwdriver  on  the  top  of  the  engine  and  bring 
the  shank  near  the  top  of  the  plug.  If  a  spark  passes 
between  the  shank  of  the  screwdriver  and  the  plug  when 
the  screwdriver  is  more  than  3/32  of  an  inch  away  from 
the  plug,  it  shows  that  the  points  in  the  plug  are  too 
far  apart.  The  correct  distance  between  points  is  1/32 
inch,  which  is  about  the  thickness  of  a  smooth  worn 
dime. 

If  the  greatest  distance  between  screwdriver  and  plug 
across  which  a  spark  will  pass  is  much  less  than  3/32 
inch,  the  voltage  of  the  coil  unit  corresponding  to  that 
cylinder  is  weak,  or  else  the  plug  is  partly  short-circuited 
by  carbon  so  that  the  current  goes  around  the  bypass  of 
carbon  inside  the  plug  rather  than  jump  from  plug  to 
screwdriver.  If  this  is  the  case,  remove  the  spark  plug 
wire  and  hold  it  about  14  inch  away  from  a  cylinder. 
If  spark  passes  from  the  wire  to  the  cylinder,  the  voltage 
is  as  it  should  be,  and  the  trouble  is  in  the  plug.  Put 
in  a  new  plug  or  else  remove  the  old  plug.  To  clean 
the  plug  thoroughly,  it  should  be  taken  apart.  To  do 
this,  clamp  the  large  hexagon  steel  shell  in  a  vise  and 
loosen  the  pack  nut  that  holds  the  porcelain  in  place. 
Scrape  carbon  from  shell  and  porcelain,  taking  care  not  to 
scrape  the  enamel  off  the  porcelain,  as  the  porcelain  will 
then  carbonize  more  easily.  Finally  wash  porcelain  and 
shell  in  gasoline.  In  reassembling  plug  do  not  tighten 
pack  nut  so  much  that  porcelain  is  cracked. 
,  If  no  spark  passed  from  plug  wire  when  latter  was 


TKOUBLES  IN  THE  POWER  PLANT 


held  within  14  incn  of  engine,  ground  the  primary  ter- 
minal on  the  coil  box,  which  corresponds  to  the  dead 
cylinder  (the  primary  terminals  are  those  in  the  top  row). 
To  do  this,  hold  the  tip  of  a  screwdriver  on  the  primary 
terminal,  and  bring  the  shank  against  the  radiator  stay 
rod.  If,  when  you  do  this,  a  spark  passes  between  the 
end  of  the  plug  wire  and  the  cylinder  when  the  wire  is 
held  y±  inch  away  from  cylinder,  the  coil  unit  is  working 
properly,  and  the  trouble  lies  in  the  wires  leading  from 
the  primary  coil  box  terminals  to  the  commutator.  Test 
these  for  short  circuit  as  described  on  page  121.  Also  ex- 
amine the  terminals  on  the  commutator  and  coil  box. 
Pull  on  the  wires  to  see  if  they  are  broken. 

Another,  and  perhaps  a  quicker  way  to  proceed  after 
locating  the  dead  cylinder,  is  to  put  in  a  coil  unit  which 
you  know  is  good,  and  put  in  a  new  plug.  If  this  stops 
the  missing  leave  new  coil  unit  and  plug  in  place. 

Still  another  method  is  to  take  the  coil  unit  from  one 
of  the  cylinders  which  is  firing  regularly  and  interchange 
it  with  the  coil  unit  corresponding  to  the  dead  cylinder 
If  the  cylinder  which  now  has  coil  taken  from  dead  cyl- 
inder now  misses,  that  coil  unit  is  defective.  If  the  orig- 
inal cylinder  still  misses,  change  the  spark  plug  with  a 
cylinder  which  is  firing  regularly.  If  cylinder  with  plug 
from  dead  cylinder  now  misfires,  that  plug  is  defective. 

If  trouble  has  not  been  found  as  yet,  try  the  following 
tests : 

(a)  Disconnect  horn  wire  from  left  hand  terminal  on 
terminal  block.     If  this  stops  misfiring,  the  horn  circuit 
is  grounded. 

(b)  Inspect  all  terminals  on  coil  box,  back  of  lighting 
and  ignition  switch  on  dash,  ammeter,  terminal  block, 
and  commutator.    Run  your  hand  along  each  wire  as  far 
as,  possible  and  feel  for  break  under  insulation.    See  that 
all  insulation  on  wires  is  not  cut,  torn,  or  oil  or  water 
soaked. 

125 


TROUBLES  IN  THE  POWER  PLANT 

(c)  See  that  contact  pieces  in  commutator  are  all 
smooth,  clean,  and  free  from  moisture  or  oil.  See  that 
insulation  between  contact  pieces  is  smooth  and  dry.  Stop 
engine  and  see  that  roller  turns  freely  on  its  pivot;  that 
the  spring  on  roller  arm  is  not  loose,  bent,  broken,  or 
too  long;  that  roller  has  no  flat  spots,  and  that  roller 
makes  good  contact  with  each  contact  piece  as  it  passes 
over  it. 

3.     BACKFIRING. 

Backfiring  occurs  when  the  mixture  is  exploded  before 
piston  has  come  near  enough  to  the  top  of  its  stroke  for 
the  momentum  of  the  flywheel  to  carry  it  over.  Back- 
firing is  not  the  explosion  of  gas  in  the  muffler.  It  is 
also  caused  by  anything  that  will  fire  the  mixture  in 
the  inlet  manifold  or  carburetor. 

A.  A  SLOW  BURNING  MIXTURE  which  burns  so 
slowly  that  it  is  still  burning  when  inlet  valves  open, 
thus  igniting  the  incoming  mixture  in  the  intake  mani- 
fold and  carburetor. 

A  mixture  which  is  too  rich  or  too  lean  will  burn 
slowly.  Poor  compression  or  incorrectly  timed  valves 
will  also  cause  slow  burning  mixtures.  If  the  mixture 
is  too  rich,  carbon  will  accumulate  in  the  cylinder  and 
finally  cause  pre-ignition  and  backfiring  by  becoming 
heated  to  incandescence. 

B.  PRE-IGNITION    DUE   TO   IGNITION    TROUBLE. 
The  most  likely  trouble  is  a  short  circuit  or  ground  in  the 
cables  leading  from  the  ignition  coils  to  the  commutator. 
Test  these  as  described  on  page  121.    It  might  also  be  due 
to  a  worn  or  dirty  commutator.     The  spark  may  be  ad- 
vanced too  far. 

C.  PRE-IGNITION    DUE    TO    OVERHEATED    CYL- 
INDERS may  be  due  to  failure  of  cooling  system,  incan- 
descent carbon  in  cylinders,  or  retarded  spark. 

In  looking  for  the  trouble,  do  the  things  that  are  easily 

126 


TROUBLES  IN  THE  POWER  PLANT 

done  and  require  but  little  time.  Advance  spark  lever. 
Examine  the  ignition  wires  for  cut,  torn  or  oil  soaked 
insulation.  Examine  commutator  for  dirt,  moisture,  or 
worn  parts.  Try  changing  the  gasoline  mixture  by  ad- 
justing the  carburetor.  Tap  the  carburetor  to  release  a 
float  which  is  stuck  to  the  walls  of  the  float  chamber.  Be 
sure  that  there  is  enough  water  in  the  radiator.  If  water 
boils,  and  steam  comes  out  of  radiator  filler  cap,  the  en- 
gine is  overheated.  To  determine  whether  there  is  in- 
candescent carbon  in  cylinders,  switch  off  the  ignition. 
If  engine  continues  to  run  with  ignition  switched  off, 
there  is  incandescent  carbon  in  the  cylinders,  or  sharp 
point  of  metal  in  the  cylinder  head  or  on  top  of  piston, 
may  have  become  incandescent. 

To  test  cooling  system  if  engine  is  hot,  stop  the  en- 
gine and  allow  it  to  cool.  Then  start  it  again.  If  the 
backfiring  occurs  before  the  water  boils,  it  is  due  to 
incandescent  carbon,  or  a  hot  point  of  metal  in  the 
cylinder.  If  water  boils  before  backfiring  begins,  the 
cooling  system  is  at  fault.  If  backfiring  begins  imme- 
diately upon  starting  engine  after  it  has  been  allowed 
to  cool,  the  cooling  system  is  not  at  fault. 

If  backfiring  occurs  immediately  after  engine  is  started 
after  having  been  allowed  to  cool  and  seems  to  be  taking 
place  in  one  cylinder  only,  locate  the  cylinder  by  ground- 
ing plug  with  screwdriver,  or  by  holding  down  one  vi- 
brator at  a  time  on  the  ignition  coils.  In  this  way  you 
will  cut  out  the  defective  cylinder,  and,  by  causing  it  to 
stop  firing,  will  eliminate  the  backfiring. 

Having  located  the  defective  cylinder,  stop  the  engine. 
Test  the  compression  of  this  cylinder  by  turning  engine 
over  slowly,  with  spark  plugs  removed  from  the  other 
cylinders.  If  compression  is  weak,  the  backfire  was  prob- 
ably caused  by  gas  leaking  out  of  cylinder  and  causing  a 
weak  mixture. 

To  locate  cause  of  weak  compression,  see  that  the  cyl- 
inder head  gasket  does  not  leak.  A  leaky  gasket  will 

127 


TROUBLES  IN  THE  POWER  PLANT 


cause  a  peculiar  squeak  when  engine  is  running  under 
load.  See  that  cylinder  head  bolts  are  drawn  down  tight. 
See  that  spark  plug  is  screwed  down  tight.  To  test  pour  a 
little  oil  around  plug  and  watch  for  gas  bubbling  through 
it.  If  the  gas  leak  is  very  bad,  the  sound  of  the  escaping 
gas  may  be  heard. 

Test  the  valve  action  by  removing  the  valve  door.  See 
that  inlet  valve  stem  is  not  too  loose  in  its  guide.  Too 
much  clearance  at  this  point  allows  too  much  air  to  be 
sucked  into  cylinders. 

If  the  backfiring  does  not  occur  regularly,  and  cannot 
be  found  by  cutting  out  several  cylinders  at  the  vibrators, 
it  is  probably  in  the  fuel  system.  Having  tried  the  car- 
buretor adjustment  without  succeeding  in  eliminating 
the  backfiring,  drain  the  gasoline  from  the  sediment  bulb 
on  the  gasoline  tank  and  carburetor  bowl.  Open  valve 
at  gas  tank  and  drain  cock  at  the  carburetor  to  see  if 
there  is  a  steady  flow  of  gasoline  in  the  supply  line. 
Also  examine  the  inlet  manifold  and  gasket  for  an  air 
leak,  by  pouring  oil  at  the  suspected  places  and  see  if 
oil  is  drawn  in. 

D.  IGNITION  TROUBLES  CAUSING  BACKFIRING. 
If  the  backfiring  occurs  while  cranking  a  cool  engine,  the 
trouble  is  probably  in  the  ignition  system. 

If  any  coil  buzzes  continuously,  the  trouble  must  be 
in  the  wires  running  from  the  coil  terminals  to  the  com- 
mutator. See  E,  Figure  20.  The  cable  containing  these 
wires  should  be  examined  for  cut,  torn,  or  oil  or  water 
soaked  insulation.  To  prove  conclusively  that  trouble 
lies  in  this  cable,  disconnect  the  wires  from  the  primary 
coil  terminals  and  commutator.  Run  an  extra  set  of  four 
separate  wires  from  the  coils  to  the  commutator.  If  this 
eliminates  the  backfiring,  the  regular  cable  is  defective, 
and  should  be  replaced. 

Other  ignition  troubles  that  may  cause  backfiring  are: 

(a)     COMMUTATOR  NOT  BEING   SET  PROPERLY. 

128 


TROUBLES  IN"  THE  POWER  PLANT 

When  the  spark  lever  on  the  steering  column  is  fully 
retarded  (up  as  far  as  it  will  go),  the  center  of  the 
commutator  case  pull  rod  should  be  2l/%  inches  from  the 
center  of  the  cap  screw  on  the  commutator  case  spring. 
If  this  distance  is  not  2y2  inches,  make  adjustment  by 
turning  the  rod  in  or  out  of  the  ball  socket  joint.  If 
this  does  not  give  enough  adjustment,  bend  the  pull  rod 
to  get  the  proper  distance. 

(b)  WET  COIL  BOX,  ESPECIALLY  IN  DAMP 
WEATHER. 

4.     KNOCKING. 

A.  CARBON.  Carbon  causes  a  short  metallic  knock 
when  the  spark  is  advanced.  An  accumulation  of  carbon 
on  the  piston  and  upper  part  of  cylinder  walls  will  reduce 
the  compression  space  sufficiently  to  cause  the  engine  to 
pound  from  excessive  pressure.  After  engine  is  warmed 
up,  the  carbon  may  become  incandescent  and  cause  pre- 
ignition  and  consequent  knocking  and  backfiring.  A  good 
way  to  test  for  carbon  is  to  shut  off  the  ignition  after  en- 
gine has  become  thoroughly  warmed  up.  If  the  engine 
continues  to  run  for  some  time  after  the  ignition  has  been 
shut  off,  the  knock  was  caused  by  carbon. 

The  increase  in  compression  caused  by  carbon  decreas- 
ing the  compression  space  gives  a  mixture  which  burns 
more  quickly,  and  the  spark  should  be  retarded  to  elimi- 
nate the  knock.  If  there  is  no  knock  when  the  engine 
is  cool,  as  when  it  is  first  started,  but  a  knock  develops 
as  the  engine  warms  up,  it  is  probably  due  to  carbon. 

The  best  way  to  remove  the  carbon  is  to  remove  the 
cylinder  head  and  scrape  off  the  carbon. 

The  Model  T  motor  lends  itself  readily  to  the  opera- 
tion of  removing  carbon.  It  is  such  a  simple  matter  to 
remove  the  head,  scrape  the  carbon  out  and  touch  up 
the  valves  that  it  is  unnecessary  to  risk  burning  or 
loading  the  seats  of  the  valves  by  burning  out  the  car- 
bon or  removing  it  with  any  of  the  many  compounds 

129 


TROUBLES  IN  THE  POWER  PLANT 


which  are  on  the  market  today.  Excessive  carbon  is 
not  only  very  annoying  because  of  its  resulting  in  knock- 
ing and  lazy  motor  action,  but  it  also  subjects  the  engine 
to  unnecessary  abuse,  resulting  in  egg-shaped  bearings 
and  burned  valves. 

Drain  the  water  from  the  cooling  system  by  opening 
the  drain  cock  on  the  radiator  outlet  connection.  If  the 
water  does  not  flow,  run  a  piece  of  wire  into  the  opening 
of  the  cock  to  loosen  the  sediment.  While  the  water  is 
running,  disconnect  the  spark  plug  wires  and  loosen  the 
plugs.  When  the  water  has  stopped  flowing,  remove  the 
capscrews  which  hold  the  cylinder  head  outlet  connection 
to  the  cylinder  head,  run  out  the  cylinder  head  cap- 
screws  and  remove  the  head,  leaving  the  screws  as- 
sembled in  it.  If  it  sticks,  drive  a  cold  chisel  between 
the  head  and  the  motor  block.  If  the  gasket  remains  on 
the  block,  remove  it  also.  The  combustion  chambers  have 
now  been  divided  in  two  parts: 

(a)  The  cylinder  head. 

(b)  The  cylinder  block  together  with  the  pistons  and 
valves. 

Remove  the  spark  plugs  from  the  head  and  insert  plugs 
of  rags  (or  better  still  of  wood  with  a  head  to  keep  them 
from  dropping  through)  into  holes  leading  into  the  water 
jacket. 

The  carbon  is  removed  by  scraping  with  an  old  file 
ground  flat  on  the  end  or  with  a  putty  knife.  After 
scraping,  the  loose  carbon  should  be  blown  off  with  com- 
pressed air  or  wiped  out  with  a  rag.  Never  use  sand- 
paper or  any  other  abrasive  material  as  it  is  likely  to 
get  between  the  cylinder  wall  and  pistons.  Scrape  any 
foreign  substance  from  the  face  of  the  cylinder  head 
and  the  head  is  ready  to  put  back  on  the  block. 

In  removing  carbon  from  the  piston  and  block,  care 
must  be  taken  that  no  carbon  gets  into  the  water  jacket 
nor  under  the  valves. 

Turn  the  motor  over  until  No.  1  piston  arrives  at  top 

130 


TEOUBLES  IN  THE  POWER  PLANT 

center  with  both  of  the  valves  closed.  Put  rags  in  No.  2 
cylinder  and  in  all  the  water  jacket  holes.  Scrape  the 
carbon  from  the  head  of  the  piston,  the  valves  and 
cylinder  block  and  blow  it  off.  Turn  the  engine  over 
so  No.  2  is  up  with  the  valves  closed,  and  this  time  put 
rags  in  No.  1  and  No.  4.  In  this  way,  proceed  until  each 
cylinder  has  been  cleaned.  With  the  end  of  a  small 
screwdriver  or  wire,  loosen  the  dirt  in  the  bottom  of  the 
capscrew  holes  and  blow  it  out  with  compressed  air  or 
with  the  foot  pump.  This  is  done  to  insure  clearance  for 
the  cylinder  head  capscrew. 

Before  putting  the  head  on,  examine  the  valves  to 
make  sure  that  there  is  no  carbon  on  the  seats.  To  insure  a 
clean  seat,  squirt  a  little  motor  oil  under  each  of  the 
valves  and  while  each  valve  is  seated,  give  it  a  few  quar- 
ter turn  oscillations  with  the  valve  grinding  tool  3-Z-604. 

The  valves  are  seated  by  turning  the  engine  over  and 
feeling  the  valves.  Until  it  is  seated,  the  valve  may  be 
turned  by  the  pressure  of  the  fingers. 

When  the  inlet  valve  of  a  cylinder  is  open,  the  ex- 
haust is  seated  and  when  the  piston  advances  past  the 
top  center  after  the  stroke  which  marks  the  descent  of 
the  inlet  valve,  both  valves  are  seated. 

Clean  the  spark  plugs.  Before  repalcing  the  head, 
make  sure  that  the  rags  are  out  of  all  the  holes  and 
scrape  any  foreign  matter  off  the  top  of  the  block. 

In  replacing  the  head,  set  No.  1  and  No.  4  pistons 
on  top  center.  If  the  spark  plugs  were  removed,  screw 
No.  4  into  place.  Examine  the  gasket,  replacing  with  a 
new  one  if  necessary.  Bend  back  the  dash  shield.  Posi- 
tion the  gasket  head  and  capscrew  assembly  by  holding 
No.  4  plug  with  the  left  hand  and  the  water  outlet  con- 
nection with  the  right.  Start  all  the  capscrews  by  hand 
before  running  any  of  them  down  with  the  wrench.  Turn 
the  engine  over  a  few  times  to  make  sure  the  pistons  do 
not  hit  the  gasket.  Run  all  the  screws  down  until  they 
seat,  then  draw  them  down  a  little  at  a  time,  crossing 

131 


TROUBLES  IN  THE  POWER  PLAOT 

from  one  end  to  the  other  of  the  head  to  draw  it  down 
evenly.  When  the  head  has  been  tightened  properly, 
replace  the  hose  connection,  making  sure  that  the  gasket 
is  in  position.  Tighten  the  spark  plugs  and  attach  the 
wires.  See  wiring  diagram  Figure  40.  Fill  the  radiator 
and  test  by  running  the  engine. 

This  is  a  better  method  than  burning.  Another  method 
is  to  use  kerosene.  Cylinders  may  be  kept  free  from 
carbon  by  removing  spark  plugs  and  pouring  a  table- 
spoonful  of  kerosene  into  the  cylinders  once  a  week.  This 
kerosene  may  be  left  in  oil  of  the  crankcase  without 
doing  any  harm. 

If  the  car  has  been  run  for  sometime  without  re- 
moving carbon,  pour  about  half  a  pint  of  kerosene  into 
the  cylinders.  Then  turn  engine  over  by  hand  until  the 
kerosene  has  drained  through  into  the  crankcase.  The 
best  time  to  do  this  is  after  the  engine  has  been  run  for 
sometime,  and  all  parts  are  warm.  The  oil  should  then 
be  drained  from  the  crankcase  and  a  new  supply  of  oil 
put  in. 

B.  PRE-IGNITION.  The  pre-ignition,  or  spark  knock, 
is  the  most  common  one.  The  gases  are  exploded  too 
soon,  tending  to  force  piston  down  before  it  reaches  the 
top  of  the  compression  stroke,  and  if  there  is  any  clear- 
ance in  any  of  the  moving  parts,  knocking  will  result.  It 
develops  when  the  engine  is  under  a  heavy  pull,  when 
running  slowly,  when  speed  is  suddenly  increased,  or 
when  climbing  hills.  The  remedy  is  to  retard  the  spark. 
If  a  car  starts  running  through  a  heavy  sandy  or  muddy 
road,  it  will  be  necessary  to  open  the  throttle  somewhat 
in  order  that  more  gas  and  air  may  be  drawn  into  the 
cylinders  to  give  the  increased  power  required.  Open- 
ing the  throttle  results  in  increased  compression  because 
a  greater  volume  of  mixture  is  drawn  into  the  cylinders 
through  the  enlarged  throttle  opening.  With  an  in- 
crease in  compression,  the  mixture  burns  more  quickly 

133 


TROUBLES  IN  THE  POWER  PLANT 


and  causes  a  pre-ignition  knock  unless  the  spark  is  re- 
tarded. The  spark  must  be  retarded  for  the  same  reason 
when  the  car  is  climbing  hills. 

If  the  commutator  is  set  improperly,  pre-ignition  and 
knocking  may  also  result.  Set  the  commutator  as  di- 
rected on  page  128. 

C.    LOOSE   OR   DEFECTIVE   MECHANICAL   PARTS. 

Some  of  the  causes  of  knocks  due  to  mechanical  causes 
are: 

(a)  Loose  or  oversized  main  bearings,  connecting  rod 
bearings,  wrist  pin  bearings,  or  camshaft  bearings. 

(b)  Poorly  fitting  time  gear. 

(c)  Transmission  out  of  line. 

(d)  Foreign  parts  in  crankcase. 

(e)  Piston  striking  cylinder  head  gasket. 

If  engine  gives  a  dull  thud  with  an  accompanying 
jarring  in  the  steering  gear  and  floorboards  when  the 
engine  is  under  a  heavy  load,  but  the  thud  is  not  notice- 
able when  engine  is  accelerated  with  clutch  out,  the  thud 
is  most  likely  due  to  a  poorly  fitting  rear  main  bearing. 

If  the  knocking  is  not  noticed  on  an  increasing  load, 
but  on  varying  the  speed,  a  single  slight  blow  is  heard 
and  felt,  either  the  flywheel  is  loose  or  there  is  too  much 
play  in  the  transmission  assembly  or  end  play  in  the  main 
bearings.  When  the  knock  is  not  accompanied  by  a 
jarring  in  the  steering  column  or  floor  boards,  it  is  in 
1  or  2  line  bearings,  connecting  rod  bearings,  wrist  pin 
or  piston. 

With  the  engine  running  at  a  fair  rate  of  speed,  cut 
out  one  cylinder  at  a  time  by  holding  down  the  vibrator 
armature  of  its  coil  unit,  accelerating  and  retarding  the 
engine  to  produce  the  knock.  If  the  knock  disappears, 
it  is  in  the  system  of  that  unit  which  has  been  cut  out. 
If,  however,  it  is  in  No.  1  cylinder,  No.  1  main  bearing 
may  be  a  loose  fit.  If  in  No.  4,  it  may  be  in  the  rear 
main  bearing.  A  piston  slap  is  a  metallic  tapping  es- 

133 


TKOUBLES  IN  THE  POWEK  PLANT 

pecially  noticeable  when  the  engine  is  cold.  A  wrist 
pin  knock  is  a  sharp  click.  Is  usually  develops  when 
driving  about  25  miles  an  hour.  A  connecting  rod  bear- 
ing knock  is  a  rapid  hollow  pounding  which  becomes 
worse  if  not  remedied.  Loose  camshaft  bearings  cannot 
be  shorted  out  as  described  above  but  can  be  readily  dis- 
tinguished by  their  rattling  sound  and  their  effect  on 
the  time  gears  which  slam  badly  when  accelerating  the 
motor,  especially  when  cold.  Sounds  are  deceiving  and 
hard  to  describe,  so  when  the  trouble  is  located  as  being 
in  a  certain  cylinder,  it  is  good  policy  to  take  out  the 
piston  and  connecting  rod  assembly  and  inspect  it  care- 
fully. 

If  the  trouble  is  located  as  being  in  No.  1,  try  taking 
up  on  the  front  bearing  bolts.  If  this  does  not  overcome 
the  trouble,  examine  the  piston  and  connecting  rod  as- 
sembly of  No.  1.  If,  by  shorting  No.  2  or  No.  3,  the 
knock  is  still  present,  cut  out  No.  2  and  No.  3  at  the  same 
time.  If  the  knock  disappears,  the  trouble  lies  in  the 
center  bearing.  If  the  knock  cannot  be  located  as  being 
due  to  one  of  the  above  causes,  it  is  probably  in  the  time 
gear  or  camshaft  or  valve.  The  knock  may  be  located 
by  listening  at  different  points  of  the  motor  with  a  rod 
or  screwdriver  placed  against  the  ear.  This  is  particu- 
larly advantageous  in  hunting  out  valve,  camshaft  or 
gear  knocks. 

A  leak  in  the  exhaust  manifold  will  sometimes  cause  a 
noise  similar  to  a  knock.  If  the  flywheel  is  scraping  the 
magneto  coils,  a  hum  will  result  and  there  will  be  no 
knock.  A  high  spot  on  the  time  gear  will  cause  a  knock 
as  the  high  spot  meshes. 

5.     ENGINE  IS  SLUGGISH,  AND  DOES  NOT  DEVELOP 

FULL  POWER. 

A.  CARBON  ON  VALVES.  As  the  motive  power  is 
obtained  by  burning  or  exploding  a  highly  compressed 
gas  mixture,  it  follows  that  a  certain  amount  of  car- 

134 


TROUBLES  IN  THE  POWER  PLANT 

bon  will  be  deposited  on  the  valve  seats,  piston  head 
and  combustion  chamber.  Small  particles  of  burnt  carbon 
will  lodge  under  a  valve,  especially  the  exhaust,  holding 
it  open.  As  this  exposes  the  valve  seats  to  the  heat 
generated  by  the  explosion,  small  pits  or  burnt  spots  will 
in  time  cause  the  surface  to  be  so  roughened  as  to  pre- 
vent the  proper  seating  of  the  valves.  This  will  cause 
a  leakage  of  gases,  resulting  in  loss  of  power  and  uneven 
running  of  the  motor.  When  this  occurs,  grinding  the 
valves  is  the  only  remedy. 

To  determine  which  valves  need  attention,  turn  the 
motor  over  slowly  by  hand  and  note  whether  the  same 
degree  of  resistance  is  met  with  in  each  cylinder.  The 
ones  offering  the  least  resistance  are  those  whose  valves 
stick.  Grinding  valves  is  the  only  remedy.  The  defect- 
ive valves  cause  loss  of  compression.  Carbon  deposits  in 
muffler  cause  back  pressure.  Tap  the  muffler  lightly 
with  a  stick  or  hammer  to  loosen  up  the  deposit  of  soot, 
which  will  then  be  blown  out  by  the  exhaust.  Mud  or 
charred  oil  may  also  stop  up  the  muffler  openings. 

B.  WORN   OR  BROKEN   PISTON   RINGS.     This   is 
sometimes  difficult  to   determine  in  advance,   especially 
if  the  valves  are  badly  carbonized  and  need  regrinding. 
By  removing  the  cap  from  the  breather  tube,  and  holding 
the  ear  to  the  opening,  you  can  sometimes  hear  the  gas 
"blowing"  past  the  rings.    Inasmuch  as  the  cylinder  head 
must  be  removed  to  replace  pistons  or  piston  rings,  it  is 
advisable  to  examine  the  valves  carefully  before  going 
farther. 

C.  LOOSE,  LEAKY  VALVES.    These  are  caused  by 

(a)  Carbon  (see  above). 

(b)  Valve    springs    weak.      Strengthen    spring    by 
stretching  it,  or  else  put  in  a  new  spring. 

(c)  Loose  Valve  Caps.    Try  with  oil  around  the  joints 
and  tighten. 

135 


TROUBLES  IN  THE  POWER  PLANT 

(d)  Insufficient  Lift  of  Exhaust  Valve. 

See  that  there  is  not  less  than  1/64  and  not  more  than 
1/32  inch  between  bottom  of  valve  stem  and  top  of  lifter, 
when  the  lifter  is  in  lowest  position  and  valve  is  on  seat. 

(e)  Valve  Push  Rods  Set  Up  Too  Tight,  causing  the 
valves  to  hold  open.     With  the  motor  hot,  test  the  push 
rod  clearance,  and  adjust  accordingly. 

D.  VALVES  NOT  TIMED  CORRECTLY.  If  inlet 
valves  open  too  late,  not  enough  charge  is  drawn  into 
cylinders.  The  valves  then  will  not  close  soon  enough 
and  some  gas  may  be  forced  out  again. 

If  inlet  valves  open  too  early,  some  of  the  burned 
gases  may  be  forced  back  through  inlet.  They  will  then 
close  before  complete  charge  has  been  drawn  into  cyl- 
inders. 

If  exhaust  valves  open  too  late,  there  will  be  back 
pressure,  and  some  of  the  burned  gases  will  be  forced  out 
through  the  inlet  valve.  Moreover,  if  exhaust  valves 
do  not  close  until  after  beginning  of  suction  stroke, 
some  of  the  burned  gases  may  be  drawn  back  into  the 
cylinder. 

If  exhaust  valves  open  too  soon,  the  burning  gases 
will  escape  before  end  of  power  stroke,  and  power  will 
be  lost.  The  valve  will  then  close  before  end  of  exhaust 
stroke,  and  not  all  the  gases  will  be  discharged. 

E.  BRAKES  DRAGGING.    Feel  break  drum  after  driv- 
ing the  car  for  some  time  without  applying  the  brakes. 
If  brake  drums  are  hot,  brakes  are  dragging,  and  need 
adjustment.     See  that  car  can  be  rolled  easily  by  hand, 
or  that  it  will  coast  down  hill  when  the  clutch  is  re- 
leased, and  does  not  slow  down.     Adjust  by  jacking  up 
rear  wheels  and  adjust  until  free. 

F.  INTAKE  MANIFOLD  LEAKS.     Try  for  leaks  by 
pouring  oil  on  joints. 

136 


TEOUBLES  IN  THE  POWER  PLANT 

G.  MIXTURE  TOO  RICH.  Caused  by  carburetor 
flooding,  probably  due  to  dirt  under  float  valve.  May 
also  be  caused  by  dash  control  not  set  properly. 

H.  MIXTURE  TOO  LEAN.  Incorrect  carburetor  ad- 
justment. Leaks  in  intake  manifold.  Also  caused  by 
poor  grade  of  gasoline. 

I.  LACK  OF  LUBRICATING  OIL.  Causes  motor  to 
have  excessive  friction  and  to  run  hot.  Introduce  kero- 
sene through  the  spark  plug  holes  in  each  cylinder  and 
crank  by  hand,  thus  cleaning  out  the  old  oil.  Drain  out 
the  kerosene  and  old  oil  at  crankcase  drain  cock.  Refill 
lubricating  system  with  correct  grade  of  oil  and  crank  by 
hand  until  engine  is  thoroughly  lubricated.  The  lack 
of  lubrication  will  also  result  in  scored  cylinder  walls. 
The  remedy  is  to  replace  worn  or  broken  rings,  and  re- 
bore  cylinders. 

J.  LACK  OF  GASOLINE.  Due  to  stoppage  in  pipe, 
or  at  the  strainer  in  the  carburetor.  Motor  will  spit 
back  through  the  carburetor  when  throttle  is  opened 
suddenly.  Poor  grade  gasoline  has  same  effect. 

K.  LACK  OF  COOLING  WATER.  Radiator  will  be- 
come hot,  and  steam  will  come  out  of  radiator  cap. 

May  be  due  to  leaky  radiator,  or  hose  connections.  If 
impure  water  has  been  used,  a  deposit  of  lime  or  scale 
may  have  gathered  in  cylinder  water  jackets,  or  in 
radiator. 

Sometimes  the  cooling  water  apparently  boils,  when  it 
is'not  hot  enough  to  do  so.  This  will  be  noticed  when 
motor  is  stopped  after  a  run,  and  is  indicated  by  a  bub- 
bling in  the  radiator.  The  cause  is  air  from  pockets 
in  the  cylinder,  bubbling  up  through  the  water  in  radia- 
tor. If  this  noise  is  noticed,  feel  radiator. 

I,    LATE  OR  SLUGGISH  IGNITION.    This  is  not  a 

137 


TKOUBLES  IN  THE  POWER  PLANT 

common  occurrence  and  is  best  detected  by  an  almost 
total  lack  of  power;  also,  the  engine  will  heat  readily, 
causing  the  water  to  boil  in  the  radiator.  If  ignition  is 
very  late,  the  engine  will  pound  and  knock  on  the 
slightest  pull.  Check  commutator  setting.  See  page  128. 

(a)  It  sometimes  occurs  that  several  strands  of  wire 
in  the  primary  circuit  (coil  to  battery  wire)  break,  and 
while  there  is  contact,  the  actual  number  of  wires  carry- 
ing the  current  may  have  been  reduced  so  as  to  increase 
the  resistance  of  the  conductor  and  cause  a  drop  of  voltage 
which  cuts  down  the  voltage  at  the  coil,  which  in  turn 
reduces  spark  strength  and  causes  slow  ignition  of  gas. 

(b)  Spark  Plug  Points  Dirty,  or  Too  Far  Apart. 

(c)  Spark  Plugs  Loose. 

6.    ENGINE    GRADUALLY    LOSES    POWER— POWER 
DECREASE  WHILE  RUNNING. 

Power  decrease  while  running  is  due  to  trouble  in  the 
carburetor  system  or  overheating.  It  is  usually  accom- 
panied by  backfire,  eventually  stopping  the  engine.  If  it 
is  in  the  carburetor,  it  is  due  to  a  stoppage  of  the  sup- 
ply line;  stop  cock  jarring  closed  in  the  gasoline  tank 
sediment  bulb;  broken  supply  line;  dirt  or  water  in  the 
carburetor;  ventilating  hole  in  the  gasoline  tank  cover 
stopped  up. 

There  may  be  a  crack  in  the  inlet  manifold  which  is 
closed  when  cool,  and  open  when  the  motor  warms  up. 
This  trouble  may  be  located  by  pouring  oil  on  the  doubt- 
ful spots. 

If  it  is  because  of  overheating,  it  will  be  noted  by  the 
water  boiling  in  the  radiator.  There  may  be  a  leak  be- 
tween the  cylinder  and  the  water  jacket  which  opens 
up  as  the  engine  becomes  warm.  This  will  cause  the 
water  in  the  heating  system  to  boil.  There  is  little  like- 
lihood of  this  occurring  anywhere  except  between  the 
gasket  and  the  cylinder  head  and  cylinder. 

If  the  valves  have  not  been  timed  after  excessive  grind- 
ing, the  stems  may  be  riding  on  the  push  rod,  and  while 

138 


TROUBLES  IN  THE  POWER  PLANT 

the  valves  would  be  seating  on  a  cool  engine,  they  would 
ride  as  the  stems  lengthened  due  to  the  heat. 

7.     IRREGULAR  ACTION  OF  ENGINE. 

By  irregular  action  we  mean  that  the  engine  misses, 
backfires,  slows  down,  and  at  times  runs  all  right.  This 
trouble  may  originate  in  either  the  carburetor  or  commu- 
tator. 

If  the  trouble  lies  in  the  carburetor,  it  is  due  to  a 
broken  spring  in  the  air  inlet  gate,  loose  jam-nut  on  the 
needle  valve,  dirt  in  the  jets,  or  poor  flow  of  gas  to  the 
carburetor. 

If  the  trouble  lies  in  the  commutator,  it  is  due  to  a 
dirty  commutator  housing,  loose  case  spring,  or  commu- 
tator roller  loose  on  shaft  or  out  of  order. 

The  first  thing  to  do  is  to  test  the  priming  rod  attached 
to  the  air  intake  gate  to  see  if  the  spring  is  in  good  con- 
dition. Next,  try  the  carburetor  adjustment,  at  the  same 
time  noticing  whether  the  needle  valve  is  too  loose. 
Surge  the  engine  to  remove  any  dirt  or  water  from  the 
jet. 

To  surge  the  engine,  move  the  gas  throttle  up  and 
down,  accelerating  and  retarding  the  engine  speed.  The 
best  way  to  surge  the  engine  is  to  drive  the  car  on  the 
road  so  the  load  of  the  car  will  be  on  the  engine.  The 
engine  should  never  be  jumped  or  raced,  as  it  is  liable  to 
score  the  bearings  or  make  them  egg-shaped. 

If  the  trouble  cannot  be  located  in  the  carburetor,  ex- 
amine the  commutator.  See  if  the  commutator  case  spring 
is  loose.  See  that  the  commutator  case  moves  freely  and 
sets  squarely  in  the  recess.  See  that  the  control  and  the 
pull  rod  are  in  good  condition.  Next  remove,  examine 
and  clean  the  commutator  and  case  and  roller. 


139 


Trouble  Shooter 


The    <g|Tg>    TEOUBLE  SHOOTEK  consists  of  three  main 
parts,  forming  a  complete   and  invaluable   system  for   quickly 
diagnosing   and   locating   any  trouble   in   the   Electric   Starting 
and  Lighting  Systems  of  all  American 
made  Automobiles. 
These  parts  are: 

(1)  The  Ambu  Instrument.  This 
is  a  combined  ammeter  and  voltmeter 
which  has  a  special  patented  set  of 
movable  dials  by  which  trouble  is 
quickly  diagnosed.  This  instrument 
may  also  be  used  as  an  ordinary  am- 
meter or  voltmeter.  The  ammeter  has 
three  scale  readings  1-0-5;  5-0-25; 
100-0-500.  The  voltmeter  readings 
0.3-0-3;  3-0-30;  15-0-150.  It  is  of  a 

very  rugged  construction  designed  for  use  in  the  repair  shop. 
(2)  Instruction  Books,  or  "Charts."  This  book  on  the 
"Ford  Standard  Electrical  Equipment"  is  typical  of  the  four- 
teen Instruction  Books,  or  "Charts"  for  the  various  makes  of 
starting  and  lighting  systems  which  form  a  part  of  the  AMBU 
Trouble  Shooter.  The  different  models  produced  by  each  maker 
are  fully  covered  in  these  charts,  there  being  instructions  for 
more  than  100  models  of  generators  and  motors. 

Each  of  these  "Charts"  gives  thorough,  yet  simple  instruc- 
tions, which  are  as  easily  understood  as  those  in  this  book  on 
the  Ford  Starting  and  Lighting  System. 

By  using  the  "Charts"  with  the  AMBU  instrument,  elec- 
trical troubles  are  easily  located  and  eliminated.  The  instru- 
ment classifies  the  trouble  and  indicates  the  exact  pages  in  the 
charts  where  the  trouble  is  described,  and  the  simplest  method 
given  for  its  location  and  removal. 

The  fourteen  "Charts"  are  of  a  convenient  size,  5%  inches 
by  7%  inches,  and  contain  more  than  3,000  pages  of  accurate, 
systematized  instructions  for  quickly  finding  and  eliminating 
electrical  troubles.  They  also  contain  over  200  circuit  dia- 
grams, arranged  in  the  same  manner  as  those  in  this  book, 
which  show  the  exact  internal  connections  of  the  various  makes 
and  models  of  generators,  motors,  regulators,  cutouts,  and  so  on. 
Other  useful  information  found  in  the  "Charts"  consist  of  ta- 
bles giving  the  lamp  equipment  of  the  various  makes  and  models 


Trouble  Shooter 

of  cars;  instructions  for  increasing  or  decreasing  the  charging 
rate  of  each  of  the  various  models  of  generators;  the  correct 
charging  rate  and  lamp  current  for  all  cars;  instructions  for 
adjusting  cutouts  and  regulators;  and  complete  descriptions  of 
the'  design,  construction,  maintenance,  and  special  features  of 
the  various  makes  and  models  of  generators,  motors,  cutouts, 
etc. 

This  data  is  all  handled  in  the  same  clear  and  concise  man- 
ner as  they  are  in  our  book,  ' i  The  Ford  Standard  Electrical 
Equipment. ' ' 

(3)  Over  700  Wiring  Diagrams,  showing  the  complete  ex- 
ternal connections  of  the  Starting,  Lighting  and  Ignition  cir- 
cuits on  cars  made  in  the  United  States  since  1911.  All  parts 
are  placed  in  the  same  relative  positions  they  occupy  on  the 
cars,  and  are  clearly  labeled  and  explained. 

In  addition  to  these  three  main  parts,  there  is  also  a  300 
page  book  telling  all  about  automobile  batteries,  their  theory, 
maintenance  and  manufacture,  and  giving  complete  and  prac- 
tical instructions  for  making  any  repairs,  charging,  etc.  This 
book  is  profusely  illustrated  by  especially  made  drawings  and 
photographs. 

A  set  of  Cadmium  Test  Leads  is  also  included;  also  a  twelve 
chapter  clearly  written  and  easily  understood  course  of  Igni- 
tion, Starting  and  Lighting;  a  complete  set  of  suggestions  for 
advertising  your  shop  in  local  newspapers,  with  the  loan  of  cuts 
and  illustrations;  and  expert  consultation  on  any  electrical  sub- 
ject. 

Ambu  is  as  Essential  to  You  as  an  Engine  is  to  an  Automo- 
bile. The  claim  made  by  Ambu  is  that  it  is  the  repairman's 
best  friend.  There  is  indisputable  evidence  to  prove  that  this 
claim  is  correct.  Men  who  have  installed  the  AMBU  TROUBLE 
SHOOTEK  Service  in  their  shops  say  they  could  not  handle  half 
the  jobs  they  do  now  if  they  did  not  have  it.  Not  only  do  they 
get  the  trade  which  comes  from  those  who  need  efficient  elec- 
trical repair  service,  but  they  are  also  able  to  make  many  hun- 
dreds of  dollars  through  the  sale  of  accessories  to  the  car 
owners  with  whom  they  are  brought  into  contact  by  AMBU. 

If  you  want  to  be  able  to  handle  any  electrical  repair  job, 
if  you  want  to  make  more  money  and  greater  profit,  get  the 
AMBU  plan,  become  an  AMBU  man. 

Complete  Trouble  Shooter Price  on  Request 


American  Bureau  of  Engineering,  Inc. 

Automobile  Department 
1603  South  Michigan  Ave.,  Chicago,   111.,   U.   S.   A, 


Battery  Steamer  and  Still 

You  can  easily  open  any  bat- 
tery without  the  use  of  a  gas 
flame  or  blow  torch  if  you  have  an 
AMBU  BATTERY  STEAMER. 
And  while  the  Steamer  is  work- 
ing away,  softening  the  sealing 
compound,  the  repairman  does 
some  other  work.  From  five  to 
thirty  minutes  and  the  sealing 
compound  is  so  soft  that  it  can 
easily  be  removed  with  the  point 
of  a  screw  driver,  and  this  will 
take  only  five  minutes,  because 
of  the  thorough  job  done  by  the 
steamer. 

Steamer  Cuts  Dirt  and  Grease. 
Another  big  advantage   of  the 

steamer  is  that  the  steam  cuts  all  the  dirt  and  grease  on  the 
battery  box  so  that  it  can  be  wiped  off  with  a  cloth,  making 
the  box  look  like  new. 

Needs  No  Attention  After  Stove  is  Lighted. 

In  the  average  battery  shop  the  wrater  supply  tank  needs  to 
be  filled  but  once  a  day.  After  that  the  stove  is  lighted  and 
the  entire  steaming  apparatus  requires  absolutely  no  attention. 
The  level  of  the  water  in  the  boiler  is  automatically  maintained 
at  one  inch.  An  automatic,  float-controlled  valve  keeps  the 
water  at  this  level  and  admits  just  enough  water  to  replace 
that  which  boils  away.  This  is  a  tremendous  advantage,  as 
steam  is  quickly  obtained,  and  a  weaker  flame  may  be  used  to 
boil  the  water. 

When  used  with  the  condenser — see  illustration — it  will  give 
five  and  one-half  gallons  distilled  water  in  seven  hours. 

Price,  complete  $35.00 

Price  without  condenser 25.00 

Price  condenser  only 12,50 

Price  steaming  box  only.  . .  12.50 


F.  O.  B.  Chicago.     Order  through  your  jobber  or  direct. 


Battery  Plate  Press 

The  most  common  fault  of  negative 
battery  plates  is  the  bulging  out  of 
the  active  material  caused  by  the 
formation  of  lead  sulphate  as  the  bat- 
tery discharges.  This  active  material 
must  be  pressed  back  flush  with  the 
i;r;ds  if  the  battery  is  to  give  good 
service  again.  Moreover,  both  posi- 
tive and  negative  plates  become  bem 
o-t  of  shape,  and  buckled,  and  must 
be  straightened. 

Many  battery  men  use  an  ordinary 
iron  bench  vise,  for  this  purpose,  but 
this  is  a  poor  practice.  The  iron  vise 
soon  becomes  corroded  and  rusted 
from  the  acid  squeezed  out  of  the 
plates.  It  also  becomes  stiff  and  hard 
to  operate.  Moreover,  there  is  always 
danger  that  particles  of  iron  will  get  on  the  plates  from  the 
vise,  and  iron  is  the  worst  enemy  of  battery  plates,  because  it 
causes  the  battery  to  lose  its  charge  quickly  and  it  is  almost 
impossible  to  remove  this  iron. 

The  AMBU  BATTERY  PLATE  PRESS  is  designed  to  do 
away  with  all  the  disadvantages  of  the  iron  vise.  Three  sets 
of  plates  may  be  pressed  at  once  between  the  large  wooden 
jaws.  No  iron  or  any  other  metal  can  touch  the  plates.  The 
upper  jaw  is  movable  and  is  operated  by  a  large  hand-wheel. 
No  acid  can  drip  on  the  operating  screw. 

A  trough  may  be  placed  under  the  press  so  as  to  catch  the 
acid  squeezed  from  the  plates.  The  trough  may  be  drained  into 
a  stone  jar  and  the  acid  saved,  thus  eliminating  the  rotted,  acid 
soaked  floor  which  results  from  the  use  of  the  iron  bench  vise, 
and  which  ruins  shoes  and  clothes. 

Fittings  with  instructions  are  furnished  with  the  Press  for 
mounting  it  on  the  wall  of  the  shop.  The  press  may  also  be 
mounted  on  a  stand,  which  is  not,  however,  furnished  with  the 
Press.  This  stand  is  easily  made  however. 

The  lower  jar  is  removable,  and  may  be  lifted  out  and  re- 
placed if  it  becomes  acid  soaked.  All  parts  are  coated  with 
acid-proof  paint. 

A  complete  set  of  transite  boards  of  the  proper  thickness  for 
placing  between  the  plates  are  included  in  the  cost  price. 
Price,  with  transite  boards,  and  fittings  for  mounting  on 

wall $32.50 

Transite  Boards  only — set  complete 5.90 

F.  O.  B.  Chicago.  Order  through  your  Jobber,  or  direct 
from  us. 

AMERICAN  BUREAU  OF  ENGINEERING,  Inc., 

Automobile    Department 
1603  S.  Michigan  Avenue  Chicago,  111.,  U.  S.  A. 


Battery  Carrier 


"Carry  a  Battery  Like  a  Suitcase." 

You  would  not  think  of  carrying  a  heavy  suitcase 
by  holding  it  in  front  of  you  with  both  hands.  Yet 
that  is  the  way  a  battery  is  generally  carried,  not  be- 
cause it  is  heavy,  but  because  of  the  way  the  handles 
are  attached  to  the  battery  box. 

WHAT  IT  IS.  The  Ambu  Battery  Carrier  consists 
of  a  stout  hardwood  handle  having  a  swinging  steel 
arm  at  each  end  to  which  is  attached  a  strong  steel 
hook  for  engaging  the  handles  on  the  battery  box. 

WHAT  IT  DOES.  The  construction  is  such  that  the 
terrific  strain  on  the  handles  of  the  battery  is  lessened 
to  a  minimum.  A  strap  with  hooks  should  never  be 
used  because  there  is  a  side  pull  that  soon  causes  the 
handles  on  the  battery  to  give  way.  Enables  you  to 
carry  a  battery  like  a  suitcase,  with  the  least  strain  on 
your  arms.  One  man  can  carry  two  batteries  at  once 
because  he  can  hold  them  down  at  his  side.  Also  use- 
ful in  lifting  a  battery  out  of  the  car,  and  putting  the 
battery  back  in  the  car.  Shipping  weight,  1  Ib.  each, 
or  2  Ibs.  per  pair. 

Price,  each $1.50 

Price,  per  pair 2.50 

F.   O.    B.    Chicago.      Order   direct   or  through   your   jobber. 


Burning  Lead    Mold 


Here's  a  convenient,  inexpensive  lead  mold  which  will  be 
quite  welcome  to  you  in  these  days  of  conservation.  Every 

battery  shop  has  an  accumulation 
of  scrap  lead  from  post  drillings, 
old  connecting  straps,  and  old 
plates. 

Such  scrap  makes  good  burning 
lead,  and  should  be  saved  until 
enough  has  accumulated  to  be 
melted  and  poured  off  into  molds. 
The  AMBU  BURNING  LEAD 
MOLD  is  made  of  heavy  sheet  iron, 
die-stamped  into  six  slots  into 
which  the  lead  is  poured.  The 
mold  gives  very  handy  sized  bars  for  lead  burning.  The  slotted 
iron  is  mounted  on  a  strong  wooden  base  which  has  a  handle  at 
one  end,  making  it  possible  to  handle  the  mold  when  full  of  hot 
lead.  A  sheet  of  asbestos  protects  the  wooden  base  from  the 
heat  of  the  melted  lead. 

The  sheet-iron  construction  absorbs  very  little  heat,  making 
it  easy  to  pour  the  lead.  This  is  a  decided  advantage  over  a 
cast-iron  mould,  which  absorbs  so  much  heat  that  the  lead  cools 
quickly  and  is  hard  to  pour. 

Price,  each $1.50 

Price,  per  pair 2.50 


F.    O.    B.    Chicago. 

Order   through    your   Jobber 

or   direct. 


Battery  Turn  Table 

When  you  once  lift  a  battery  up  on  the  work  bench,  you  do 
not  want  to  move  it  around  any  more  than  necessary.  It  is  too 
heavy  for  easy  handling.  Yet  in 
lead  burning,  sealing,  repairing  the 
handles,  repairing  the  case,  or 
painting  the  case,  you  often  must 
be  able  to  get  at  all  sides  of  the 
battery. 

To    eliminate  the   back-breaking 
lifting  and  turning  around  of  the  BATTERY  TURN 


battery,  the  AMBU  BATTERY  TURNTABLE  was  designed. 
Every  battery  man  should  have  at  least  one  of  these  handy  turn- 
tables. A  battery  on  this  turntable  can  be  turned  around  with 
one  finger. 

The  turntable  is  not  fastened  to  the  work  bench,  and  may  be 
taken  to  the  battery,  instead  of  carrying  the  heavy  battery  to  it. 

It  is  made  of  well-seasoned  hardwood  and  will  last  for  years. 
Price,  each  ..........................  ..................  $2.50 

F.  O.  B.  Chicago.  Your  Jobber  can  supply  you  now.  If  not, 
write  to  us  direct. 


Cadmium  Voltmeter 


In  order  to  make  accurate  Cad- 
mium Tests,  you  must  have  a  fine 
reading  voltmeter.  Most  ordinary 
voltmeters  are  not  suitable  for  this 
purpose,  and  to  get  a  voltmeter  oi' 
sufficient  accuracy,  you  usually  pay 
from  $r>0.00  to  $100.00. 

The  AMBU  CADMIUM  VOLT- 
METER is  made  especially  for  Cad- 
mium Tests,  and  is  therefore  abso- 
lutely certain  to  give  you  accurate 
results. 

A  complete  instruction  book  for 
making  Cadmium  Tests  goes  with 
each  instrument. 

Voltmeter   only $22.50 

Voltmeter  with  Cadmium  Leads  25.00 

Your  jobber  can  supply  you  now. 
If  not  write  direct. 


Large  Rack 


Plate  Burning  Racks 

When   you   burn-in   new   plates,    or 

attach  a  whole  group  of  plates  to  a 

plate  strap,  you  need  a  burning  rack 

to  hold  the  plates   in  position  while 

the  lead  is  melted  in. 

WHAT    THEY    ARE.      The    Ambu 

Plate    Burning    Racks    have    guiding 

slots   cut   in   the   base   as   well   as   in 

the    iron    bar,    or    "comb."      In    this 

way   the   plates   are   held    at   exactly 

the    right    distance    apart,    both    at 

the  top  and  bottom.     Bases  are  made 

of   hardwood.      The    small    rack    will 

take   care  of  practically   all    %    inch 

plates  made  by  Willard,  Gould,  Phil- 
adelphia, and  U.  S.  L.     It  will  also  accommodate  all  thin  plates  such 

as  the  Exide  3XC,  Willard,  and  Gould.     The  large  rack  will  take  care 

of  many  other  types,  being  designed 
to  accommodate  fully  05  per  cent  of 
all  the  types  of  plates  which  are 
made  at  present. 

Special  iron  fittings  are  furnished 
which  are  placed  around  the  plate 
lugs  on  the  comb  so  as  to  hold  the 
plates  firmly  in  position,  and  to  pre- 
vent the  hot  lead  from  running  off. 
WHAT  IT  DOE'S.  Enables  you  to 
bum  in  plates  in  half  the  time  re- 
quired when  using  the  ordinary  rack. 
Plates  are  held  at  exactly  the  cor- 
rect distance  apart.  The  hot  lead 
cannot  run  off.  No  iron  touches  the 
bottoms  of  the  wet  plates. 

Shipping  weight  of  small  rack.  1.0 
Ibs.  Shipping  weight  of  large  rack, 
15  Ibs. 

Price   of   small   rack $  7.50 

Price  of  large  rack 12.50 

F.   O.    B.   Chicago.      Order   direct   or  through   your   jobber. 


Small   Rack 


Cadmium  Leads 

How  often  you  have  said,  "If 
I  only  had  some  way  of  know- 
ing which  set  of  plates  is  in  a 
bad  condition,  without  first 
opening  up  the  whole  battery!" 
That  is  precisely  what  you  can 
do  with  the  AMBU  CADMIUM 
LEADS.  These  Cadmium 
Leads  consist  of  two  heavily  in- 
sulated flexible  wires,  each  five  feet  long,  at  one  end  of 
which  are  brass  prods  with  wooden  handles,  and  at  the 
other  end  of  which  are  forked  terminals  for  attaching  to 
the  voltmeter.  Fastened  at  right  angles  to  one  of  the  brass 
prods  is  a  rod  of  chemically  pure  cadmium. 

With  these  AMBU  CADMIUM  LEADS  you  can  make 
absolutely  reliable  tests  in  a  few  moments,  and  you  must 
have  the  means  to  make  such  tests  if  you  want  to  know 
whether  each  set  of  plates  is  functioning  properly,  and  able 
to  give  good  service  while  under  load.  The  Cadmium 
Test  will  show  up  a  poor  set  of  plates,  be  they  positive  or 
negative  plates,  instantly.  No  battery  should  be  taken  off 
the  charging  bench,  or  sent  out  of  your  shop  until  a  Cad- 
mium Test  shows  that  both  positive  and  negative  plates 
are  fully  charged  and  ready  to  give  good  service. 

Give  this  matter  your  immediate  consideration.  Order 
now.  Can  be  used  with  any  voltmeter  that  has  readings 

as  fine  as  five  hundredths. 
I 

CADMIUM  LEADS  .. . . $3.25 

Order  through  your  Jobber  or  direct.  . 


1917-1918-1919 


Automobile 

Wiring 

Diagrams 


Ambu  diagrams  were  the  original  simplified 
wiring  diagrams.  They  were  placed  first  in 
the  hands  of  the  garagemen  as  part  of  the 
Famous  Ambu  Electrical  Trouble  Shooter, 
They  were  never  before  obtainable  except  with 
the  Trouble  Shooter,  Each  diagram,  6x9,  is 
printed  on  the  strongest  kraft  paper  in  intense 
black  ink.  Easy  to  read,  handy  to  refer  to, 
and  lasting  for  years.  No  symbols  are  used. 
These  diagrams  simplify  electrical  problems, 

1919  Edition  of  wiring  diagrams  contains 
sets  for  cars  made  in  1917,  1918  and  1919, 
Diagram  for  each  model  of  car.  They  are 
bound  in  loose  leaf  form  allowing  for  additions 
of  new  diagrams  as  they  appear  or  for  dia- 
grams of  cars  made  previous  to  1917  which 
may  be  secured  in  single  form, 

1919  Edition........ .$3,50 

Single  diagrams  of  all  cars,  191 1  to  present.— 25c 

Order  through  your  jobber  or  direct. 


The  Automobile  Storage  Battery 


Chapter  1. 
Chapter  2. 
Chapter  3. 
Chapter  4. 
Chapter  5. 
Chapter  6. 
Chapter   7. 
Chapter  8. 
Chapter  9. 
Chapter  10. 
Chapter  11. 
Chapter  12. 
Chapter  13. 


It's  Care  and  Repair 

This  book  tells  in  non-technical 
language  all  that  you  want  to 
know  about  handling  and  repair- 
ing the  Automobile  Storage  Battery. 

Price  delivered  in  the  United 
States...  _  $5.00 


CHAPTER  HEADINGS 


SECTION    I. 

Introductory. 

Batteries  in  General. 

Chemical  Actions  which  Produce  Electricity. 

How   Chemical   Actions   Produce   Electricity. 

Ix>ss  of  Charge  in  an  Idle  Battery. 

The  Discharge  Phenomena. 

The  Charge   Phenomena. 

Capacity  of   Storage  Batteries. 

Internal  Resistance. 

Battery   Diseases. 

Conditions  of  Operation. 

How  to  Take  Care  of  the  Battery  on  the  Car. 

Manufacture  of  Storage  Batteries. 


SECTION  II. 

Chapter  14.  The  Workshop.  General  Instructions.  The  Workshop, 
Shop  Equipment,  Special  Work  Bench,  Shelving-,  Concerning  Light, 
Charging  Methods,  Charging  Equipment,  Double  Charging  Bench,  Mo- 
tor-Generator Sets,  Mercury  Arc  Rectifier,  Electrolytic  Rectifier,  Dis- 
charge Board,  Tools  and  Equipment,  The  Battery  Steamer,  The  Battery 
Plate  Press,  Battery  Turntable,  The  Burning  Lead  Mold.  Tagging-  Bat- 
teries, Precautions  to  be  taken  by  the  Repairman,  Lead  Burning,  Sav- 
ing the  Sediment,  Mixing  Electrolyte. 

Chapter  15.  Analysis  of  the  Condition  of  the  Battery.  What  Is 
the  Trouble?  Cutout  Adjustments,  Battery  Trouble  Charts,  Summary 
of  Work  to  be  done  on  the  Battery.  When  May  a  Battery  b«  Left  on 
the  Car?  When  Should  a  Battery  be  Removed  from  the  Car?  When 
is  it  unnecessary  to  open  the  Battery?  When  must  a  Battery  be 
Opened? 

Chapter  16.  Work  on  the  Battery.  Charging  Batteries  Before  Re- 
building. How  to  Open  a  Battery.  What  must  be  Don*  with  the 
Opened  Battery?  Wh.en  to  Put  in  New  Plates.  When  the  Old  Plates 
may  be  Used  Again.  Separators.  Freeing  Shorts.  Charging-,  Washing 
and  Pressing.  Burning  on  Plates.  Reassembling  the  Elements.  Re- 
pairing- the  Case.  Putting  in  New  Jars.  Putting  Elements  in  Jars. 
Filling  Jars  with  Electrolyte.  Putting  on  the  Covers.  Sealing-  Com- 
pounds. Sealing  the  Battery.  Burning-  in  the  Connecting  Straps  with 
Hydrogen  and  Oxygen  Flame.  Burning  in  the  Connecting  Straps  with 
Soldering  Irons.  Cleaning  and  Painting  the  Case.  Charging  the  Re- 
built Battery.  Discharging  and  Testing. 

Chapter  17.  Special  Instructions.  Willard  Type  S  Batteries,  Exide 
Batteries,  Presto-lite  Batteries.  U.  S.  L.  Batteries. 

Chapter  18.      Cadmium  Test,   Storing  Batteries,   Finished  Work. 
Your    Jobber    can    supply    you    now,    or    order    direct. 


Armature  Tester 


AMBU  ARMATl/(?E 


This  is  an  accurate,  positive  device  for  quickly  detecting  and  accu- 
rately locating  open  circuits,  short-circuits,  grounds,  and  reversed 

commutator  connectors  on  the  arma- 
tures of  motors  or  generators  which 
are  equipped  with  commutators. 

WILL  TEST  ANY   SIZED 

ARMATURE. 

Any  sized  armature,  no  matter  how 
small  or  large,  no  matter  what  its  re- 
sistance, may  be  tested  with  equal 
facility.  No  connections  are  made  to 
the  armature,  and  the  armature  need 
not  be  removed  from  the  machine  if 
it  is  possible  to  get  at  the  commutator. 

MAY   BE   USED   ON   ANY   A.    C.    OR    D.    C,   CIRCUIT. 

The  AMBU  ARMATURE  TESTER  may  be  used  on  any  direct  or 
alternating  current  circuit,  and  on  any  voltage  from  6  to  220.  No 
change  or  adjustment  is  necessary  in  changing  from  a  direct  to  an 
alternating,  or  from  alternating  to  direct,  current  circuit.  For  the 
various  voltages,  it  is  only  necessary  to  use  lamps  of  the  proper 
voltage  or  no  lamps  at  all,  as  the  case  may  be. 

CONSTRUCTION   IS   VERY    SIMPLE. 

Current  from  the  supply  circuit  is  led  through  a  current  inter- 
rupter, which  is  bridged  by  a  condenser.  The  current  is  sent  into 
each  consecutive  pair  of  segments  through  the  Contact  Making  Pins 
shown  in  the  illustration.  The  two  Transformer  Arms  shown  in  the 
illustration  touch  the  commutator  also,  and  lead  to  the  telephone  re- 
ceiver circuit  through  a  specially  designed  transformer  coil. 

INDICATIONS  ARE  POSITIVE. 

The  variation  in  the  sound  heard  in  the  receiver  tells  what  the  na- 
ture of  the  trouble  is,  and  just  where  it  is.  In  making  a  test,  the 
contact  making  pins  are  brought  down  on  each  pair  of  consecutive 
segments,  the  Transformer  arms  resting  on  the  commutator  several 
segments  on  either  side  of  the  contact  making  pins. 

This  testing  is  all  done  with  one  hand.  An  open  circuit  is  indi- 
cated by  a  sudden  and  marked  louder  sound,  a  short-circuit  by  a  sud- 
den and  marked  dimmer  sound,  reversed  commutator  connections  by- 
louder  sounds  on  every  second  pair  of  segments  as  long  as  they  last. 
Grounds  are  located  by  testing  between  each  segment  and  the  arma- 
ture core  or  shaft.  The  segment  which  is  nearest  the  grounded  point 
of  the  winding  is  indicated  by  a  sudden  dimming  of  the  sound  in  the 
receiver. 

THE  AMBU  ARMATURE"  TESTER  has  been  in  daily  use  in  a 
large  armature  repair  shop  for  over  three  years,  and  has  been  given 
a  thorough  and  severe  tryout.  There  is  nothing  to  get  out  of  order, 
no  delicate  or  adjustable  parts. 

The  entire  outfit  weighs  less  than  seven  pounds,  and  may  be  easily 
carried  about. 


Price,    each    $30.00 

F.    O.   B.   Chicago.      Your   Jobber   can  supply  you,   or  order   direct. 


UNIVERSITY  OF  CALIFORNIA  LIBRARY 
This  book  is  DUE  on  the  last  date  stamped  below. 

Fine  schedule:  25  cents  on  first  day  overdue 

50  cents  on  fourth  day  overdue 
One  dollar  on  seventh  day  overdue. 


NEERINQ  LI 


APR    3  1951 


LD  21-100m-12,'46(A2012sl6)4120 


UNIVERSITY  OF  CALIFORNIA  LIBRARY 


